Cosmology with Ground-Based VHE Gamma-Ray Detectors

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002.tex 644 34 12 5434 5555513720 5323 % Session 10 -- Gamma Ray Sources
Display presentation, Monday, 30, 1994, 9:20-6:30

[10.02] Cosmology with Ground-Based VHE Gamma-Ray Detectors

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik)

Active Galactic Nuclei (AGN) and Superclusters of Galaxies, considered to be possible sources for the observed flux of extremely high energy cosmic rays ($E \geq 10^{19} \, \rm eV$), may well have $\gamma$-ray emission extending into the VHE (very high energy, $E_\gamma>100$ GeV) domain. Because VHE $\gamma$-rays are absorbed by pair production on the intergalactic background radiation fields, much of this emission may not be directly visible. The electromagnetic cascade initiated by the absorbed VHE $\gamma$-rays, however, is observable. Since, the velocities of $e^{+}e^{-}$ pairs produced in the cascade are most probably isotropized by an ambient random magnetic field, extended `halos' ($R > 1 \, \rm Mpc$) of pairs will be formed around AGN with VHE emission. The cascade radiation from these pair halos is emitted almost isotropically and should be observable at energies below a few TeV. The $\gamma$-ray flux from a halo depends mainly on the total luminosity and duty cycle of the source at energies $\geq 10$ TeV, but not on the source geometry, in particular the direction and beaming/opening angle of a $\gamma$-ray emmiting jet. (The halo emission is not beamed.) The halo radiation can be distinguished by its characteristic variation in spectrum and intensity with angular distance from the central source. This depends on the distance to the source and the level of the $IR/O$ background of the local enviroment. Thus, the investigation of the angular and spectral distribution of halo radiation could provide almost model-independent and unambiguous cosmological information about the universal $IR/O$ background, the Hubble constant, and the VHE power of AGN. Next-generation ground-based systems (arrays) of low threshold ($E \geq 100 \, \rm GeV$) imaging Cherenkov telescopes will be able to probe the VHE apparent luminosities of extragalactic sources down to $L \approx 10^{43}(d/1000 \, \rm Mpc)^{2} \, \rm erg/s$, which is two orders of magnitude lower than the minimum luminosity detectable by EGRET at GeV energies. The excellent angular resolution expected from these systems ($\approx 0.1 \deg$) will allow us to image pair halos of even cosmologically distant ($z \geq 1$) sources.

ROSAT Observations of the May 1 1992 Gamma Ray Burst Source

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S1003.tex 644 34 12 3304 5555513475 5325 % Session 10 -- Gamma Ray Sources
Display presentation, Monday, 30, 1994, 9:20-6:30

[10.03] ROSAT Observations of the May 1 1992 Gamma Ray Burst Source

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC)

The gamma-ray burst of May 1 1992 was observed and rapidly localized by the 3rd Interplanetary Network, and a 2000 s ROSAT TOO observation was carried out on the small error box. A weak x-ray source was detected, but with too few photons to determine the spectral and temporal characteristics of the source. We have recently carried out a 30 ksec PSPC observation of this source, resulting in the detection of 140 photons. We find that the spectrum is consistent with thermal bremsstrahlung from a 7 million degree plasma with about $10^{22} cm^{-2}$ column depth. In addition, analysis of the photon arrival times indicates that the source is variable. The distance implied by the column depth makes it unlikely that this source is coronal emission from a field star. Optical and HRI observations of this region are now planned or underway. We discuss the possible identification of this object and its implication for the GRB source. ing jet. (The halo emission is not beamed.) The halo radiation can be distinguished by its characteristic variation in spectrum and intensity with angular distance from the central source. This depends on the distance to the source and the level

A Search for Short Duration Bursts of Gamma Rays above 10$^{14}$ eV using CASA-MIA

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the $IR/O$ background of the local enviroment. Thus, the investigatS1004.tex 644 34 12 3743 5555513543 5331 % Session 10 -- Gamma Ray Sources
Display presentation, Monday, 30, 1994, 9:20-6:30

[10.04] A Search for Short Duration Bursts of Gamma Rays above 10$^{14}$ eV using CASA-MIA

\newbox\grsign \setbox\grsign=\hbox{$>$} \newdimen\grdimen \grdimen=\ht\grsign \newbox\simlessbox \newbox\simgreatbox \setbox\simgreatbox=\hbox{\raise.5ex\hbox{$>$} \llap {\lower.5ex\hbox{$\sim$}}} \ht1=\grdimen\dp1=0pt \setbox\simlessbox=\hbox{\raise.5ex\hbox{$<$} \llap {\lower.5ex\hbox{$\sim$}}} \ht2=\grdimen\dp2=0pt \def\simgreat{\mathrel{\copy\simgreatbox}} \def\simless{\mathrel{\copy\simlessbox}} \newbox\simppropto \setbox\simppropto=\hbox{\raise.5ex\hbox{$\sim$} \llap {\lower.5ex\hbox{$\propto$}}} \ht2=\grdimen\dp2=0pt \def\simpropto{\mathrel{\copy\simppropto}} P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah)

CASA-MIA is a ground based array which detects the air-showers produced by gamma-rays at 100 TeV and above. The array's ability to detect muons allows much of the cosmic-ray background to be discarded. Data from 1990 to 1993 has been used to search for short duration gamma-ray bursts from arbitrary direction. No evidence for 0.035s bursts has been found. This result has been used to set a limit on the rate-density of evaporating primordial black holes. Additional point source searches with longer time windows of 1s, 10s and 100s are also investigated. ays above

Comments on the Accuracy of Angular Clustering Tests Used to Study Repeating Gamma-Ray Bursts in BATSE Data

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$^{14}$ eV using S1005.tex 644 34 12 2743 5555512306 5325 % Session 10 -- Gamma Ray Sources
Display presentation, Monday, 30, 1994, 9:20-6:30

[10.05] Comments on the Accuracy of Angular Clustering Tests Used to Study Repeating Gamma-Ray Bursts in BATSE Data

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), ()

Comparisons are made of various techniques used to identify gamma-ray burst repeaters in BATSE data. The effectiveness of each test is examined when BATSE positional errors and incomplete sky sampling are folded into the data analysis. Techniques studied include the two-point angular correlation function, the nearest neighbor statistic, and the farthest neighbor statistic. Comments are made concerning the observed incidence of repeaters in BATSE's First Burst Catalog. This work has been supported by NASA grants NAG8-192 and NRA 92-OSSA-17.

Integral Moment Analysis of the BATSE Burst Intensity Distribution: Comments on Two-Population (Local Disk/Halo Plus Extended Halo) Models

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rays at 100 TeV and above. S1006.tex 644 34 12 2553 5555512307 5326 % Session 10 -- Gamma Ray Sources
Display presentation, Monday, 30, 1994, 9:20-6:30

[10.06] Integral Moment Analysis of the BATSE Burst Intensity Distribution: Comments on Two-Population (Local Disk/Halo Plus Extended Halo) Models

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH)

Moment analysis of the gamma-ray burst log(N>Fp) vs. log(Fp) distribution observed by BATSE is used to place additional constraints on Galactic coronal/extended halo source distributions. It is found that the allowed parameter space of such models is smaller than identified previously (Hakkila et al. 1994, Proc. 1993 Hunts. Workshop) due to the more efficient tolerances impose by this technique. This work has been supported by NASA grant NAG8-192. Burst Catalog. This work has been supported by NASA grants NAG8-192 and NRA 92-OSSA-17.

What Happened to M51 and M81?

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rays at 100 TeV and above. S101.tex 644 34 12 3112 5555513401 5225 % Session 1 -- Brouwer Prize Lecture
Oral presentation, Monday, 30, 1994, 8:30-9:20

[1.01] What Happened to M51 and M81?

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT)

On this occasion, I plan to review the evidence that has accumulated from observations and numerical experiments during especially the past decade suggesting that each of these two famous spiral galaxies has been influenced decisively by recent tidal interplay with their respective close neighbors. It is no secret that I am biased: Like a few other astronomers, I have long suspected on dynamical grounds that the magnificent spiral structures which have brought these two galaxies into nearly every introductory textbook (and the latter also onto the cover of the Hubble Atlas) are largely transient wavelike relics of those tidal interactions --- meaning that we would probably have favored some quite different examples had mankind come along just 200 million years earlier or later. But I will try to keep such biases well under control in this review of the recent developments achieved almost entirely by workers other than myself. In other words, this talk will focus not only those portions of the tidal stories which seem well established, but also on some parts which remain shaky.

iscuss the possible identification of this object and its implication for the GRB source. ing jet. (The halo emission is not beamed.) The halo radiation can be distinguished by its characteristic variation in spectrum and intensity with angular distance from the central source. This depends on the distance to the source and the level

The Evolving Radio Jet in BL Lacerta

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the $IR/O$ background of the local enviroment. Thus, the investigatS1101.tex 644 34 12 4347 5555513502 5323 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.01] The Evolving Radio Jet in BL Lacerta

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan)

During the past 15 years, there have been at least ten outbursts at centimeter wavelengths in this extragalactic object. We describe here the flux density and linear polarization variations observed at 4.8, 8.0 and 14.5~GHz with the Michigan 26-meter telescope during the series of outbursts since 1987. The recent bursts are somewhat different from the highly polarized bursts in the early 1980s, which provided a successful quantitative test of a source model based on propagating transverse shocks in a relativistic jet. The most notable change is that the polarization position angle during polarized outbursts has increased by approximately 10 degrees. This is approximately the same shift as found in a comparison of VLBI maps taken during the same time periods by Mutel, Denn and Dryer (1994, NRAO Workshop on Compact Extragalactic Radio Sources , ed. Zensus and Kellermann, p. 191), and supports their conclusion that the orientation of the radio emitting jet in BL~Lac has changed over time. Our preliminary analysis further suggests that a simple scaling of the physical parameters which gave quantitatively good fits to both the 1982 and 1983 bursts will not accurately describe the recent, relatively isolated, burst in 1991. We also note that while some bursts (e.g. in 1982, 1983 and 1991) exhibit degrees of linear polarization in excess of ten percent, other bursts (e.g. in 1980 and 1990) exhibit a very low degree of linear polarization. A common characteristic of the low polarization events is that they all exhibit high internal synchrotron self absorption (as indicated by the flux density spectra of the outbursts).

This research has been supported in part by NSF grant AST-9120224. beamed.) The halo radiation can be distinguished by its characteristic variation in spectrum and intensity with angular distance from the central source. This depends on the distance to the source and the level

EUVE spectrographic results on the BL Lac Object PKS 2155-304

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the $IR/O$ background of the local enviroment. Thus, the investigatS1102.tex 644 34 12 2114 5555513305 5313 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.02] EUVE spectrographic results on the BL Lac Object PKS 2155-304

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron)

We present spectra of PKS 2155--304 obtained by the Extreme Ultraviolet Explorer (EUVE) satellite during two long ($>100,000$~s) observations taken three weeks apart. Each spectrum shows pronounced, but different, absorption features. We discuss mechanisms that might produce these features. We use these results to rule out various models for the object that have been suggested based on X-ray results. This work has been supported by NASA contract NAS5-30180. meters which gave quantitatively good fits to both the 1982 and 1983 bursts will not accurately describe the recent, relatively isolated, burst in 1991. We also note that while some bursts (e.g. in 1982, 1983 and 1991) exhibit degrees of linear polarization in excess of ten percent, other bursts (e.g. in 1980 and 1990) exhibit a very low degree of linear polarization. A common characteristic of the low

Pictor A: Discovery of Strong Balmer Line Variations

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larization evenS1103.tex 644 34 12 3757 5555513745 5342 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.03] Pictor A: Discovery of Strong Balmer Line Variations

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.)

We have detected strong changes in Balmer line flux and profile shape for the Broad Line Radio Galaxy Pictor A (0518--458). Comparison of spectra obtained in 1983 and 1993 reveal that strong broad line component has appeared with FWHM$\sim$400 \AA. The Balmer lines observed in 1993 are reminiscent of the rare kind (extremely broad profiles with shifted ``humps'') observed in Arp 102B, 3C390.3 and a handful of other BLRGs. Earlier observations of Pic A show much narrower and weaker broad line emission, with a centrally peaked profile and with monotonically falling line wings.

The emission line profile widths and redshift are consistent with emission from an inclined relativistic accretion disk but the relative strength of the red and blue ``humps'' are not. Considerable excess flux is observed on the red side of the profiles. It might be possible to reconcile the observations with a disk model if we assume that a ``hot spot'' co-rotating with the disk contributes to the line emission.

The rarity of Pic A--like profiles however suggests that the radial velocity spread is maximized if the orientation is such that the gas is predominantly moving along the line of sight. We show that a system of outflowing clouds (possibly a double shell) in a bi-conical geometry can reproduce the profile and the profile variations.

3cm Observations of the Extended NW radio Jet in Pictor A

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the investigatS1104.tex 644 34 12 2647 5555513465 5337 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.04] 3cm Observations of the Extended NW radio Jet in Pictor A

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF )

We present high--resolution, 3\,cm radio synthesis images of Pictor A constructed from four 12--hour sets of observations with the ATCA (Australia Telescope Compact Array). We find that the kiloparsec--scale radio jet located between the nucleus and the NW radio--optical hotspot, which lies more than 100\,kpc from the central galaxy, has an unresolved width ($\sim$ 1 \arcsec \, or 500 $h^{-1}$\,pc). This jet is not completely straight, but changes direction between RA 5h\,20m\,35s and 5h\,20m\,40s. The SE and NW hotspots are not alligned with the nucleus. The eastern segment of the unresolved jet points towards the nucleus while the western segment, if extended to the east, intersects the SE hotspot. Near the central host galaxy, the 3\,cm continuum structure seems to be closely related to loops of ionized, H\,II gas (on a 2 to 4\,kpc scale).

Observations of `Flicker' in Extragalactic Radio Sources.

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uthor{S1105.tex 644 34 12 4567 5555513150 5332 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.05] Observations of `Flicker' in Extragalactic Radio Sources.

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan)

We present the initial results of The University of Michigan Radio Astronomy Observatory's `flicker' program. The `flicker' sources are compact or very compact QSOs and BL Lac objects that have been found to vary by 10 -- 20\% in flux, on time scales of hours to days (Quirrenbach, et al., Astr. Ap., 226, L1 1989), in contrast to the month to year time scale of variability traditionally thought to characterize these objects. The short timescales of this variability can help to provide us with information on structure currently beyond the reach of VLBI. This variability must also be taken into account when making synthesis maps of sources which may vary significantly in flux over the time period when they are observed.

We have made closely spaced observations at 4.8, 8.0 and 14.5 GHz using The University of Michigan's 26-meter radio telescope so as to extend the variability program started in the 1960s down to time scales of hours to days. The emphasis in our program has been to confirm the variability on time scales of hours to days as well as to better define variability on scales of days to weeks. The goal is to attempt to determine if the nature of the variations on these intermediate time scales is different for the `flicker' sources (where the variations appear to peak at lower frequencies) as compared to the traditional sources (where variations peak at higher frequencies and can be explained by a shocked jet model). We have also done Monte Carlo type simulations to simulate flicker phenomena. We hope that the simulations will help us to better understand what features of the light curves are due to small scale turbulent structure, and determine to what extent single dish observations can be used to test quantitatively models of such flows.

This research has been supported in part by NSF grant AST-9120224 HE apparent luminosities of extragalactic sources down to $L \approx 10^{43}(d/1000 \, \rm Mpc)^{2} \, \rm erg/s$, which is two orders

Spectropolarimetry of the Broad Absorption Line QSO 1524+5147

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S1106.tex 644 34 12 4521 5555513021 5316 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.06] Spectropolarimetry of the Broad Absorption Line QSO 1524+5147

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO)

Broad absorption line QSOs (BALQSOs) comprise approximately 10\% of all optically-selected quasars, and as a class are the only such objects to exhibit strong ($>3$\%), static linear polarization. Observations of the emission line and continuum properties of BALQSOs suggest that all radio-quiet QSOs are potential BALQSOs, being observed as such if the line of sight intercepts an absorbing cloud. The unique insight which polarimetry lends to the geometry of a source of radiation therefore motivates intense study of the accessible BALQSO candidates.

Optical linear spectropolarimetry is presented of the high-redshift (z = 2.86) BALQSO 1524+5147, an object selected for its brightness (V = 17.0) and strong white-light polarization (P = 2.7\%). In the rest frame of the object (1070 - 1940\AA), the degree of continuum polarization is nearly constant with wavelength, and the position angle is undeviated through the spectrum. The broad emission lines (BELs) provide pure dilution of the polarized component, while BAL features primarily absorb this component.

These conditions indicate a single, nuclear source of polarized radiation, but constant polarimetric properties over a 3.5 yr baseline suggest that synchrotron emission is not responsible. Instead, we propose that the polarization arises in an asymmetric distribution of scatterers which are coincident with and/or interior to the BAL and BEL regions, and the latter two need not be distinct. The bluer spectrum of polarized vs. total flux suggests either that the scatterers are dust grains or that an additional, red component of unpolarized light contributes to the overall continuum. These properties are discussed in terms of competing models of the nuclear morphology of AGN.

This research is supported by NSF grant AST 91-14087. 20224 HE apparent luminosities of extragalactic sources down to $L \approx 10^{43}(d/1000 \, \rm Mpc)^{2} \, \rm erg/s$, which is two orders

Time Variable Associated Absorption in the QSO UM 675

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S1107.tex 644 34 12 4627 5555512761 5340 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.07] Time Variable Associated Absorption in the QSO UM 675

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD)

We discuss dramatic changes in the $z_a \approx z_e$ absorption system of the $z_e = 2.15$ QSO UM 675 (Q0150$-$203). The C IV $\lambda$1550 and N V $\lambda$1240 doublets at $z_a = 2.1344$ strengthened by a factor of $\sim$3 between the observations of Sargent, Boksenberg and Steidel (1988, ApJS, 68, 539; measured November 1981) and our earliest measurements (November and December 1990). During this time, C IV in the $z_a = 2.0083$ system may also have strengthened. The variability of other lines in these systems is unknown. Continued monitoring is in progress.

We consider several models of the $z_a \approx z_e$ absorption environment, and conclude that the absorbing clouds are close to the QSO and photoionized by the QSO continuum. The variability timescale ($\lap$2.9 yrs rest) requires gas densities $\gap$4000 cm$^{-3}$ to allow changes in the ionization balance. This minimum density, and the high ionization needed to produce the Ne VIII $\lambda$774 and O VI $\lambda$1035 absorptions reported previously (E. M. Burbidge et al. , 1993, BAAS, 24, 1135), requires clouds $\lap$200 pc from the QSO. The full range of absorption line ionizations (including C III $\lambda$977 and N III $\lambda$989) implies that the clouds are segregated, spanning a factor of $\gap$10 in distance or $\gap$100 in density. Across these regions the H I fraction varies from $\sim$10$^{-3}$ to $\sim$10$^{-6}$. The total hydrogen column ranges from a few times $10^{18}$ cm$^{-2}$ in the low ionization gas to $\sim$10$^{20}$ cm$^{-2}$ where the Ne VIII lines form. The Lyman continuum is expected to be optically thin throughout, consistent with the measured absence of a Lyman edge. The metal abundances are roughly solar or above. Implications of these results are discussed.

This work is supported by NASA grant NAG 5-1630.

ion angle is undeviated through the spectrum. The broad emission lines

Optical-UV-Soft-X-ray Spectra of AGN

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ELs) provide pure dilution of tS1108.tex 644 34 12 3421 5555512727 5332 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.08] Optical-UV-Soft-X-ray Spectra of AGN

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO)

The physical origin of the much studied optical/UV ``Big Bump'' in quasars is unknown. Even its suggestive connections with ``soft X-ray excesses'' is uncertain. We have investigated several models for the blue bump and the soft X-ray excess: (a) free-free emission from an optically thin plasma (see Barvainis 1993 for a review), (b) optically thick thermal emission from the innermost regions of an accretion disk in both Schwarzschild and Kerr geometries (e.g., Shields 1978, Malkan \& Sargent 1982, Czerny \& Elvis 1987, Sun \& Malkan 1989, Laor 1990, Fiore, $et al.$ 1994). We present the locus of each model in optical/UV/soft X-ray color-color diagrams. The colors were optimized to be indicators of particular spectral components and they provide stronger discriminants than the standard UBV diagrams. These diagrams clarify the limitations of both models in their pure form. Addition of extra components is needed and we show how the simplest possible addition (an underlying power law) brings disk models into agreement with the data. We compare our results with the sample of 47 low z quasars for which we have collected observations over a wide range of frequencies (Elvis $et al.$ 1994). d, we propose that the polarization arises in an asymmetric distribution of scatterers which are coincident with and/or interior to the BAL and BEL regions, and the latter two need not be distinct. The bluer \newcommand{\MgII}{Mg\,{\small II}}

Associated Mg\,II Absorption in Red Quasars

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ectrum of polarized vs. totaS1109.tex 644 34 12 3144 5555512725 5333 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.09] Associated Mg\,II Absorption in Red Quasars

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO)

In a spectroscopic survey of 56 intrinsically faint, steep-spectrum quasars, we detected an excess of quasars with associated \MgII\ absorption line systems, in which $z_{abs} \approx z_{em}$. This is in contrast to other surveys using apparent magnitude selected samples which have found no such excess above the background expected from distributed absorbers. In our sample there is a strong correlation between very red rest-frame B-V colors of the quasar and the presence of associated \MgII\ absorption. In order to further understand this result, we have obtained deep R-band images of two of the red quasars (3C\,68.1 and 3C\,212) and begun a spectroscopic survey of quasars selected for very red B-V color. In 3C\,68.1 ($z=1.24$), we observe a prominent extension outside the quasar point source, and what is most likely a foreground cluster. Spectroscopy of three faint red quasars revealed no associated \MgII\ absorption lines. The implications of these results are discussed. results with the sample of 47 low z quasars for which we have collected observations over a wide range of frequencies (Elvis $et al.$ 1994). d, we propose that the polarization arises in an asymmetric distribution of scatterers which are coincident with and/or interior to the BAL and BEL regions, and the latter two need not be distinct. The bluer

HST and Ground-Based Spectroscopy of High Luminosity AGNs

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ectrum of polarized vs. totaS1110.tex 644 34 12 3321 5555512700 5311 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.10] HST and Ground-Based Spectroscopy of High Luminosity AGNs

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison)

We are carrying out quasi-simultaneous multiwavelength spectrophotometry from below Ly $\alpha$ to beyond H $beta$ for a sample of $\sim 50$\ radio-loud quasars with $z \sim 0.3$\ to 1.3. The aim is to understand the structure and physics of the nuclear environment -- through investigations of the Baldwin effect, comparison of line profiles and ratios, continuum shape, and X-ray and radio properties. In particular the sample is selected with constrained radio lobe luminosity, but with a wide range in the ratio of radio core to lobe flux density. We use the latter ratio as a prime indicator of orientation of the central engine, thus enabling us to investigate angle dependence of kinematics, optical depth, and anisotropy of the broad-band continuum. We will present some striking results derived from our sample, which is so far about 60\% complete.

Manchester} P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison)

We are carrying out quasi-simultaneous multiwavelength spectrophotometry from below Ly $\alpha$ to beyond H $beta$ for a sample of $\sim 50$\ radio-loud

Compact Double Radio Sources in the MIT-Green Bank-VLA (MGV) Gravitational Lens Search Sample

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asars with $z \sim S1111.tex 644 34 12 2642 5555512674 5331 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.11] Compact Double Radio Sources in the MIT-Green Bank-VLA (MGV) Gravitational Lens Search Sample

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT)

We have made radio and optical observations of a selection of compact double radio sources discovered in the course of the the MIT-Green Bank-VLA gravitational lens search. These sources were chosen for followup by virtue of having two or more unresolved components separated by less than two arcseconds in VLA A-array maps at X Band (3.6 cm). Statistical studies have shown that the class of ``compact double radio sources'' are not, in general, larger objects seen end-on. This class is not well-studied at the present time, but they appear to be radio galaxies at large redshifts. We will present results from our 6 cm MERLIN observations of a sample of these sources. We will also present preliminary results of our optical followup program using the 1.3m McGraw-Hill telescope.

a foreground cluster. Spectroscopy of three faint red quasars

A New Technique for Identifying High Redshift Quasars

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vealed no associated \MgII\ S1112.tex 644 34 12 3027 5555514227 5324 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.12] A New Technique for Identifying High Redshift Quasars

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory)

This report presents preliminary results of a search for high redshift quasars based on the Palomar Transit Grism Survey of Schmidt, Schneider \& Gunn. The original survey covers $\sim$ 60 square degrees of the sky with low-resolution slitless spectra of approximately 600,000 objects in the wavelength range from 4400~{\AA} to 7500~{\AA} and was designed to find emission line candidates of a given signal--to--noise ratio and equivalent width.

Our goal is to establish whether there is a significant number of high redshift quasars with weak or narrow emission lines by searching for objects with a continuum depression blueward of the Lyman break. In addition to providing an interesting sample of quasars with different emission line properties, these objects could explain the steep decline in the comoving space density of strong emission line quasars at redshifts higher than $\sim$ 2.5. The follow--up observations will be carried out with the new spectrograph at the 3.5m ARC Telescope, Apache Point, NM.

implications of these results are discussed. results with the sample of 47 low z quasars for which we have collected observations over a wide range of frequencies (Elvis $et al.$ 1994). d, we propose that the polarization arises in an asymmetric distribution of scatterers which are coincident with and/or interior to the BAL and BEL regions, and the latter two need not be distinct. The bluer

Very High Energy Gamma-Ray Observations of Markarian 421

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ectrum of polarized vs. totaS1113.tex 644 34 12 3514 5555512522 5322 % Session 11 -- Luminous AGN and QSOs
Display presentation, Monday, 30, 1994, 9:20-6:30

[11.13] Very High Energy Gamma-Ray Observations of Markarian 421

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U)

Markarian 421 is the closest (z=0.031), yet dimmest identified AGN observed by EGRET. As yet, it is also the only AGN to be observed at TeV energies by the Whipple Observatory imaging gamma-ray telescope. The energy spectrum of Mrk421 between 0.3 GeV and 4 TeV was previously reported to be 1.02x$10^{-11} E^{-2.06}$ photons/cm$^{2}$/s/TeV. At TeV energies, this represents a 6$\sigma$ excess above background. However, the EGRET and Whipple observations used to determine the spectrum were not taken contemporaneously. Previous EGRET and Whipple observations showed no strong evidence of variablility. In April 1994, Markarian 421 was observed with both the Whipple telescope and EGRET. The preliminary results of the Whipple observations in the energy range between 0.25 TeV and 10 TeV will be reported. Of special interest are energies above 3 TeV where the effects of intergalactic absorption from the IR background should become noticeable. distribution of scatterers which are coincident with and/or interior to the BAL and BEL regions, and the latter two need not be distinct. The bluer

The Effects of Dust on the Ultraviolet Spectral Energy Distribution of Starburst Galaxies

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ectrum of polarized vs. totaS1201.tex 644 34 12 4765 5555514256 5337 % Session 12 -- Starburst Galaxies
Display presentation, Monday, 30, 1994, 9:20-6:30

[12.01] The Effects of Dust on the Ultraviolet Spectral Energy Distribution of Starburst Galaxies

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo)

The effects of dust on the spectral energy distribution (SED) of starburst regions of galaxies was investigated using Monte Carlo techniques to model the transport of radiation in systems where the dust and stars are mixed. In a recent paper, Calzetti, Kinney, \& Storchi-Bergmann (ApJ, 10 July 1994) derive an extinction curve from observations of starburst galaxies assuming the dust is in a screen geometry. This gives an extinction curve where the geometrical effects of mixing of the dust and stars are convolved with the extinguishing effects of the dust. The resulting extinction curve is greyer than the Galactic extinction curve and featureless in the ultraviolet, i.e. lacking both the 2200 \AA\ bump and far-UV rise.

In an attempt to explain this ``effective'' starburst extinction curve we have modeled the effects of dust on the SED of starbursts. A simple starburst model was used to determine the different populations of stars as a function of the starburst age. The flux at 23 wavelengths, ranging between 1000 \AA\ to 5500 \AA\, was computed using Monte Carlo techniques assuming the dust and stars were spherically distributed. The dust was assumed to have similar properties as dust in our Galaxy. The distribution of different star types ranged from mostly centrally located for O stars to constant density for A and later stars. In addition, the fraction of stars lying outside the dust ranged from very few for O stars to a majority for A and later stars. Combining the two models, it was found that the SED was strongly dependent on the distribution of the different types of stars relative to the dust, the age of the starburst, and the amount of dust. The ``effective'' UV extinction curve became greyer and featureless as the amount of dust was increased. For example, the 2200 \AA\ bump was almost non-existent for large amounts of dust.

This work was supported by NASA LTSA Grant NAGW-3168.

o orders

Spectroscopic Observations of Hot Spot Galaxies

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S1202.tex 644 34 12 2531 5555513367 5327 % Session 12 -- Starburst Galaxies
Display presentation, Monday, 30, 1994, 9:20-6:30

[12.02] Spectroscopic Observations of Hot Spot Galaxies

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College)

Long-slit spectroscopic observations of hot spot galaxies NGC 4321 and NGC 2903 will be presented. These galaxies display knots of radio and optical emission in their nuclear regions which suggest regions of intense star formation. Spectroscopic observations taken with the Kitt Peak 2.1m will be compared with radio and H-alpha images of these galaxies. Spectra of the optical hot spots reveal strong variations from spot to spot in the nature of the underlying continuum. Emission-line ratios in the nuclear regions also display a wide range of physical properties among the hot spots. These nuclear line ratios are significantly different from line ratios in comparison HII regions in the disks of these spriral galaxies. Optical spectra of knots of non-thermal radio emission will also be presented.

extinction curve we have modeled the effects of dust on the SED of starbursts. A simple starburst model was used to determine the different populations

Off-Center Star Formation in The Nuclear Starburst Galaxy NGC 2903

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stars as a S1203.tex 644 34 12 2035 5555513672 5326 % Session 12 -- Starburst Galaxies
Display presentation, Monday, 30, 1994, 9:20-6:30

[12.03] Off-Center Star Formation in The Nuclear Starburst Galaxy NGC 2903

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison)

NGC 2903 is a strongly barred galaxy harboring a nuclear starburst. We have mapped the 1.28$\mu$m Pa-$\beta$ recombination line using CRSP, the KPNO long-slit near IR spectrograph, on the KPNO 1.3m telescope. The map shows that star formation is strongly concentrated about 3" or 150pc to the north of the nucleus. We discuss the advantages and disadvantages of our observational technique compared to conventional narrow band and Fabry-Perot imaging.

display a wide range of physical properties among the hot spots. These nuclear line ratios are significantly different from line ratios in comparison HII regions in the disks of these spriral galaxies. Optical spectra of knots of non-thermal radio emission will also be presented. extinction curve we have modeled the effects of dust on the SED of starbursts. A simple starburst model was used to determine the different populations

Multi-wavelength Observations of Galaxy Pairs in the Early Stages of Merger

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stars as a S1204.tex 644 34 12 2271 5555513643 5327 % Session 12 -- Starburst Galaxies
Display presentation, Monday, 30, 1994, 9:20-6:30

[12.04] Multi-wavelength Observations of Galaxy Pairs in the Early Stages of Merger

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA)

Multi-wavelength observations of interacting galaxy pairs provide a view the early stages of the merger process. VLA 21cm HI observations and H$\alpha$\ imaging provide evidence of minor-axis gas outflows, as well as the funneling of gas into the nuclei of some galaxies (Arp 270 and Arp 283). Observations are ongoing for other systems that appear to be at about the same stage of interaction as these pairs. Comparisons are made between the near-infrared and HI, as well as optical and ROSAT PSPC observations in order to understand further this type of star formation in colliding systems. ing CRSP, the KPNO long-slit near IR spectrograph, on the KPNO 1.3m telescope. The map shows that star formation is strongly concentrated about 3" or 150pc to the north of the nucleus. We discuss the advantages and disadvantages of our observational technique compared to conventional narrow band and Fabry-Perot imaging.

A Radio Continuum Survey of Ring Galaxies

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nS1205.tex 644 34 12 3517 5555513177 5336 % Session 12 -- Starburst Galaxies
Display presentation, Monday, 30, 1994, 9:20-6:30

[12.05] A Radio Continuum Survey of Ring Galaxies

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.)

As part of a multi-wavelength study of interacting galaxies with ring-like structure, we observed 13 systems with the VLA in D-array at 8.4 GHz. Four objects were also observed at 1.4 GHz and 4.8 GHz. Snapshots of 15-20 minutes were done to identify candidates for future deeper and higher resolution observations. Nine of the 13 objects were detected at X-band above a threshhold of about 0.2 mJy. Results will be compared with H-alpha and infrared observations of these objects to study star formation processes in the wake of a density wave resulting from a collision. The regions of recently formed O/B stars are expected to be bright in H-alpha and radio thermal bremstrahlung radiation. The internal optical extinction in the star formation regions can in principle be estimated by comparisons of H-alpha and radio thermal flux, thus allowing the stellar composition of the star clusters in these regions to be deduced. We expect that diffusion of relatavistic electrons from supernova sites results in non-thermal radiation that lags behind the sites of young star formation, the latter being richer in thermal radiation. Our preliminary results for ARP 10 are consistent with this scenario in that we find the flattest spectrum part of the radio map coincides with the region of brightest H-alpha flux. ntrally located for O stars to constant density for A and later stars. In addition, the fraction of stars lying outside the

A Spectrophotometric Study of Ring Galaxies

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st ranged from very few for O stars to a majority S1206.tex 644 34 12 2142 5555513716 5327 % Session 12 -- Starburst Galaxies
Display presentation, Monday, 30, 1994, 9:20-6:30

[12.06] A Spectrophotometric Study of Ring Galaxies

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU)

We present our analysis of longslit spectrophotometric data for a sample of ring galaxies. A detailed calculation of the radial variation of chemical abundances is used to examine the star formation history and possible collisional nature of these systems. We focus our attention on Arp 10, a peculiar ring galaxy, which exhibits an azimuthal variation of the star formation rate along the ring. Such a behavior is consistent with a collisionally induced density wave. We estimate the kinematics inferred from the spectra and present a plausible scenario of the evolution of the galaxy. ormed O/B stars are expected to be bright in H-alpha and radio thermal bremstrahlung radiation. The internal optical extinction in the star formation regions can in principle be estimated by comparisons of H-alpha and radio thermal flux, thus allowing the stellar composition of the star clusters in these regions to be deduced. We expect that diffusion of relatavistic electrons from supernova sites results in S12071207.tex 644 34 12 7173 5555513613 5647

Where Does Star Formation End in Disk Galaxies?

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st ranged from very few for O stars to a majority S1206.tex 644 34 12 2142 5555513716 5327 % Session 12 -- Starburst Galaxies
Display presentation, Monday, 30, 1994, 9:20-6:30

[12.07] Where Does Star Formation End in Disk Galaxies?

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory)

Much work has focused on understanding the key processes which govern star formation in galactic disks and a major goal has been to establish the link between star formation activity and the physical and dynamical state of the interstellar medium. An important issue is how star formation ends in disks. Does it end abruptly, or is there a smooth decline in star formation activity? Is the location of the outermost HII region determined solely by galaxian properties, or is there a dependence on the local environment? Are there sites of recent star formation beyond the ``edge" of the old stellar disk?

HII regions are the clearest tracers of present day massive star formation. In order to address the above issues, we have undertaken a deep H$\alpha$ imaging study of the outer regions of a sample of spiral galaxies. Our sample includes both field and Virgo cluster galaxies which have been mapped in HI. We will present some preliminary data from which we have identified a number of galaxies with HII regions located at large galactocentric radii. These regions often lie beyond the critical radius for star formation predicted by simple gravitational instability theories. We will discuss these data and investigate the possible implications for disk evolution.

Where Does Star Formation End in Disk Galaxies?

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st ranged from very few for O stars to a majority S1206.tex 644 34 12 2142 5555513716 5327 % Session 12 -- Starburst Galaxies
Display presentation, Monday, 30, 1994, 9:20-6:30

[12.07] Where Does Star Formation End in Disk Galaxies?

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory)

Much work has focused on understanding the key processes which govern star formation in galactic disks and a major goal has been to establish the link between star formation activity and the physical and dynamical state of the interstellar medium. An important issue is how star formation ends in disks. Does it end abruptly, or is there a smooth decline in star formation activity? Is the location of the outermost HII region determined solely by galaxian properties, or is there a dependence on the local environment? Are there sites of recent star formation beyond the ``edge" of the old stellar disk?

HII regions are the clearest tracers of present day massive star formation. In order to address the above issues, we have undertaken a deep H$\alpha$ imaging study of the outer regions of a sample of spiral galaxies. Our sample includes both field and Virgo cluster galaxies which have been mapped in HI. We will present some preliminary data from which we have identified a number of galaxies with HII regions located at large galactocentric radii. These regions often lie beyond the critical radius for star formation predicted by simple gravitational instability theories. We will discuss these data and investigate the possible implications for disk evolution. star formation predicted by simple gravitational instability theories. We will discuss these data and investigate the possible implications for disk evolution.

Star Formation Rates in Low Surface Brightness Galaxies

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st ranged from very few for O stars to a majority S1206.tex 644 34 12 2142 5555513716 5327 % Session 12 -- Starburst Galaxies
Display presentation, Monday, 30, 1994, 9:20-6:30

[12.08] Star Formation Rates in Low Surface Brightness Galaxies

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon)

The low surface brightness (LSB) disk galaxies found in recent surveys (e.g.,\ Schombert et al.\ 1992, AJ, 103, 1107) tend to be blue and gas rich. These properties along with their low mean surface luminosity and {\sc H i} densities imply an inefficient mode of star formation. The H$\alpha$ images that we present of a sample of these galaxies show the weak star formation in these galaxies relative to high surface brightness, Hubble sequence spirals. Most LSB disks harbor only a handful of widely scattered {\sc H ii} regions and generally have low total H$\alpha$ fluxes. However, in some cases these scattered areas of star formation can be quite vigorous. For example, the giant LSB disk galaxy F568-6 contains a complex that is comparable in size, mass, and star formation rate to a luminous irregular galaxy, but contributes only about 5\% of the galaxy's total blue luminosity (Bothun et al.\ 1990, ApJ, 360, 427). We present neutral hydrogen images of some of the largest known LSB galaxies. The gas in these galaxies is distributed in regularly rotating, giant, and also very low {\sc H i} surface brightness disks. A preliminary analysis shows that if most of the gas is in atomic hydrogen, large parts of the disks have total surface densities below the threshold for star formation to set in.

s Hopkins University,\\ Dept. of Physics and Astronomy\\

Early Results from the HST Medium Deep Survey with WFPC2

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st ranged from very few for O stars to a majority S1206.tex 644 34 12 2142 5555513716 5327 % Session 12 -- Starburst Galaxies
Display presentation, Monday, 30, 1994, 9:20-6:30

[12.09] Early Results from the HST Medium Deep Survey with WFPC2

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI)

We present some of the initial results from the HST Medium Deep Survey (Key Project) using WFPC2 in cycle 4. WFPC2 has been used in parallel mode for the survey at the rate of a few fields every week since late January 1994, where each field is typically covered by several 30-40 minute "orbits", with exposures split between "wide V" (F606W) and "wide I" (F814W). The extragalactic part of ther Medium Deep Survey is directed towards an understanding of galaxy morphology at intermediate redshifts (0.1 to 0.7), with systematic ground-based spectroscopic and photometric follow-up.

Some of the initial WFPC2 images show evidence for compact, superluminous starburst regions within galaxies. We also detect a high fraction of disturbed and interacting systems, and estimates are made of these fractions relative to local galaxies.

We are performing a search for serendipitous objects, and present images of candidate lensing systems and merging/interacting galaxies.

ing the two models, it was found that the SED was strongly dependent on the distribution of the different types of stars relative to the dust, the age of the starburst, and the amount of dust. The ``effective'' UV extinction curve became greyer and featureless as the amount of dust was increased. For example, the 2200 \AA\ bump was almost non-existent for large amounts of dust. This work was supported by NASA LTSA Grant NAGW-3168. o orders

Global Oscillations in Near-Critical Accretion Flows

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S1301.tex 644 34 12 5441 5555514066 5327 % Session 13 -- Models or Gas Flows and Spectral Formation
Display presentation, Monday, 30, 1994, 9:20-6:30

[13.01] Global Oscillations in Near-Critical Accretion Flows

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University)

Bright accretion-powered systems exhibit many varieties of time-variabilty, including flaring and quasiperiodic oscillations. These may reflect variations in the source itself intrinsic to rapid accretion; to assess this idea we examine the time-dependent response of radiation-dominated spherical accretion flows to radial and nonradial perturbations. Such flows may serve as useful first approximations to the actual accretion flows in low-mass X-ray binaries (LMXBs) and other systems. Feedback between the production of radiation and the flow of gas to the radiation producing regions promotes the existence of global modes, each of which is associated with a characteristic oscillation about steady flow. The feedback mechanism is very general, implying that radiation hydrodynamic oscillations may be a universal feature of rapidly accreting systems. These oscillations are accompanied by characteristic variations in the radiation output of the accretion flow. Because heavily damped modes are unlikely to be observable, we examine how the frequencies and the damping rates of global modes depend on parameters such as the mass accretion rate. Under conditions thought to be typical of LMXBs, the radial modes are weakly damped and some nonradial modes are even linearly unstable. Our results for the frequencies and structure of radial modes confirm similar findings by Fortner, Lamb, and Miller~(1989). When nonradial modes are active, the flow develops regions through which material preferentially accretes, and regions through which radiation preferentially escapes. Our linear stability analysis suggests that these modes dominate the accretion flow behavior when the system luminosity approaches the Eddington limit, the critical point beyond which steady spherical accretion becomes impossible. Nonradial mode frequencies behave very differently from those of the radial modes, as they appear to depend only weakly on the system luminosity. A connection may exist between nonradial radiation hydrodynamic modes and the NB/FB quasi-periodic intensity oscillations found in LMXBs, which also display striking frequency stability.

Subsonic Accretion through Stellar Boundary Layers

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S1302.tex 644 34 12 2322 5555513344 5321 % Session 13 -- Models or Gas Flows and Spectral Formation
Display presentation, Monday, 30, 1994, 9:20-6:30

[13.02] Subsonic Accretion through Stellar Boundary Layers

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center)

Recent progress$^{1,2}$ in the application of numerical relaxation techniques has made possible the construction of steady-state boundary-layer solutions for thin alpha-disks around accreting unmagnetized stars. Physically acceptable solutions must satisfy the constraint that the radial inflow velocity not be supersonic. Preliminary results on new models of subsonic accretion will be presented.

Supported in part through KBN grant 2-1244-91-01. \par\noindentReferences \hfil \par\noindent 1. Paczy\'nski, B. 1991, ApJ 370, 597-603. \par\noindent 2. Popham, R. \& Narayan, R. 1992, ApJ 394, 255-260. ion producing regions promotes the existence of global modes, each of which is associated with a characteristic oscillation about steady flow. The feedback mechanism is very general, implying that radiation hydrodynamic oscillations may be a universal feature of

Radiation drag near slowly rotating neutron stars

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pidly accreting systems. These osciS1303.tex 644 34 12 4641 5555513633 5331 % Session 13 -- Models or Gas Flows and Spectral Formation
Display presentation, Monday, 30, 1994, 9:20-6:30

[13.03] Radiation drag near slowly rotating neutron stars

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign)

In a previous paper (Miller \& Lamb 1993) we showed that radiation forces are more important than general relativistic corrections to Newtonian gravitational forces in determining the motion of particles accreting onto a nonrotating, isotropically emitting neutron star if the luminosity is greater than $\sim$1\% of the Eddington critical luminosity $L_E^\infty$, even if the radius of the star is less than the radius of the innermost stable orbit. We also showed that at luminosities greater than $\sim 0.2L_E^\infty$, a substantial fraction of the accreting matter can transfer most of its angular momentum and gravitational binding energy to the radiation field before reaching the stellar surface.

Here we extend this work to include slow rotation of the gravitating mass and radiation source, as well as radiation from ring-like boundary layers. By ``slow rotation" we mean that the azimuthal velocity of the radiating source is $v/c\ll 1$ and that the dimensionless angular momentum of the gravitating mass is $j\equiv cJ/GM^2\ll 1$; for all neutron stars with measured rotation periods $j<1$, so this is a good approximation. We find that, compared to particle motion around nonrotating stars, the rate of radiation drag is decreased for prograde motion around rotating sources. However, because the drag time is increased, the total energy and angular momentum transfered from the particle to the radiation field can actually be increased compared to the nonrotating case. We conclude that in any disk-accreting neutron star source, radiation drag will have a significant qualitative effect on particle motion. This work was supported in part by NASA grant NAGW 830 at the University of Chicago and by NSF grant PHY 91-00283 and NASA grant NAGW 1583 at the University of Illinois. omes impossible. Nonradial mode frequencies behave very

Effects of Superfluidity on Nonradial Oscillations of Neutron Stars

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fferently from those of the radial mS1304.tex 644 34 12 3326 5555514223 5325 % Session 13 -- Models or Gas Flows and Spectral Formation
Display presentation, Monday, 30, 1994, 9:20-6:30

[13.04] Effects of Superfluidity on Nonradial Oscillations of Neutron Stars

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab)

In the limit of short wavelengths, it has been shown that superfluidity significantly affects wave propagation in neutron stars. Here we abandon the short-wavelength restriction and extend these calculations to global oscillation modes. In particular, we derive the equations of motion for spheroidal oscillations, including superfluid effects. These modes are global generalizations of one of the classes of waves considered previously. In the present modal analysis of a neutron star, we use a three component neutron star model, which consists of a fluid ocean, a solid crust, and a fluid core. The solid crust is divided into an outer crust and an inner crust, and a superfluid of neutrons coexists with the solid lattice in the inner crust. We have computed several low-order global spheroidal modes for $l=2$ both with and without superfluidity. We find that the existence of superfluid in the inner crust affects the frequency spectra of acoustic (p-) modes, shear (s-) modes, and interfacial modes, although the suface g-modes are not affected at all by the superfluid. s a good approximation. We find that, compared to particle motion around nonrotating stars, the rate of radiation drag is decreased for prograde motion around rotating sources. However, because the drag time is increased, the total energy and angular momentum transfered from the particle

Multidimensional Relativistic Hydrodynamics

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the S1305.tex 644 34 12 2626 5555514377 5342 % Session 13 -- Models or Gas Flows and Spectral Formation
Display presentation, Monday, 30, 1994, 9:20-6:30

[13.05] Multidimensional Relativistic Hydrodynamics

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois)

In this work we present a formulation of the Riemann solver for relativistic hydrodynamics. The Riemann solver presented here is an extension to the relativistic regeime of the high quality, two shock Riemann solver for non-relativistic hydrodynamics presented by Van Leer (1979) and Colella (1982). It, therefore, shows the same advantages that the previously mentioned reimann solvers show for non-relativistic hydrodynamics, viz. exact treatment for strong shocks and accurate treatment of contact discontinuities. We then incorporate the riemann solver into a multidimensional TVD algorithm and show that the algorithm allows one to calculate with precision several flows with very high Lorenz factors ( i.e. flows with speeds very close to the speed of light). Applications to astrophysical flows will be presented.

heroidal modes for $l=2$ both with and without superfluidity.

Numerical Simulations of Narrow Angle Tailed Radio Sources : The Jones and Owen Model

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find that the existence of superfluid in S1306.tex 644 34 12 2561 5555514411 5326 % Session 13 -- Models or Gas Flows and Spectral Formation
Display presentation, Monday, 30, 1994, 9:20-6:30

[13.06] Numerical Simulations of Narrow Angle Tailed Radio Sources : The Jones and Owen Model

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois)

In previous work, Balsara and Norman (1992), we had focussed on simulating narrow angle tailed radio sources as fluid beams that are bent by the ram pressure of a cross flowing ICM. This allowed a comparison with several observable attributes of NAT sources. In particular we were able to make estimates of bending rate, beam profile, radial evolution and formation and interspacing of knots. The previous work suffered from the fact that the ISM of the host galaxy was not represented. In this work we remove that restriction by representing the host galaxy's ISM self-consistently using the prescription given in Balsara, Livio and O'Dea (1994). We then run jets through it and compare with observations.

d. heroidal modes for $l=2$ both with and without superfluidity.

Galaxies in Clusters : Gas Stripping and Accretion

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find that the existence of superfluid in S1307.tex 644 34 12 2265 5555514375 5341 % Session 13 -- Models or Gas Flows and Spectral Formation
Display presentation, Monday, 30, 1994, 9:20-6:30

[13.07] Galaxies in Clusters : Gas Stripping and Accretion

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA)

We study the process of a galaxy moving through the intercluster gas in a cluster of galaxies, using a high quality hydrocode run at high resolutions. We find that ram pressure strippingoccurs in the form of individual events that are separated by about ten million years. In addition we find that the galaxy accretes gas from the downstream side into the core. This accretion process exhibits a radial "pumping" mode, similar to the one found previously in simulations of wind accretion onto compact objects. Some implications of our results for the understanding of a few recent observations are discussed.

{07}

Galaxies in Clusters : Gas Stripping and Accretion

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find that the existence of superfluid in S1307.tex 644 34 12 2265 5555514375 5341 % Session 13 -- Models or Gas Flows and Spectral Formation
Display presentation, Monday, 30, 1994, 9:20-6:30

[13.07] Galaxies in Clusters : Gas Stripping and Accretion

Free-Free Radiation Cannot Make\\the UV/Soft-X-Ray Excess in AGN

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ffil{ Space TeS1308.tex 644 34 12 3656 5555514331 5337 % Session 13 -- Models or Gas Flows and Spectral Formation
Display presentation, Monday, 30, 1994, 9:20-6:30

[13.08] Free-Free Radiation Cannot Make\\the UV/Soft-X-Ray Excess in AGN

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU)

Thermal gas always has associated atomic spectral features either in absorption or in emission. In optically thin gas the emission spectrum is dominated by line radiation and recombination continua. An example of radiation from optically thin material in accreting systems is the emission-line-dominated spectrum of a cataclysmic variable in its low state.

Barvainis (1993, ApJ, 412, 513) and others have proposed that the UV/soft-X-ray excess prominent in the spectra of many AGN is due to free-free emission from gas at temperatures of $10^5 - 10^6$ K. Simple arguments using only atomic data show that the recombination radiation from emission lines would produce UV, optical, and soft X-ray spectral features orders of magnitude stronger than observed. Collisional excitation produces even more line radiation under most physical conditions.

As a particular example I take the Astro-1 observations of the Seyfert 1 galaxy Mrk 335 by HUT and BBXRT. Depending on the ionization state of the gas (which may be photoionized by the central source), the emission measure of the free-free radiation necessary to produce the UV continuum ($3 \times 10^{68} \rm cm^{-3}$ at $8.2 \times 10^5$ K for $\rm H_o = 75~km~s^{-1}~Mpc^{-1}$) implies line emission from O VI, O VII, or O VIII more than a factor of 10 stronger than any features observed by HUT or BBXRT.

reased, the total energy and angular momentum transfered from the particle

Accretion Disk Modeling of Lyman Edge \\ Features in the HUT Spectrum of 3C 273

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the S1309.tex 644 34 12 4324 5555514416 5335 % Session 13 -- Models or Gas Flows and Spectral Formation
Display presentation, Monday, 30, 1994, 9:20-6:30

[13.09] Accretion Disk Modeling of Lyman Edge \\ Features in the HUT Spectrum of 3C 273

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University)

We obtained far-ultraviolet spectra of the quasar 3C 273 using the Hopkins Ultraviolet Telescope (HUT) during the flight of Astro-1 aboard the space Shuttle Columbia in December 1990. The HUT spectra cover the 830-1850 \AA\ wavelength range with a resolution of $\sim$3 \AA. In two successive orbits we accumulated 3389 s of high quality data. Approximately 750 s of the total were obtained during orbital night. Our spectra extend well past the Lyman edge down to a wavelength of 787 \AA\ in the rest frame of this z=0.158 quasar.

The HUT spectrum shows a steeply rising continuum in the far ultraviolet with a distinct break to a flatter slope at 1128 $\pm$ 3.5 \AA\, just longward of the redshifted Lyman edge of 3C 273. The continuum shape is empirically well characterized by a broken power law in $F_\lambda$ with a spectral index of 1.6 at wavelengths longer than 1128 \AA\ and 0.2 at shorter wavelengths. We propose that the break and the flattening of the continuum may be due to Lyman edge features in the spectrum of an accretion disk. We model the spectral shape in the Lyman edge region using an $\alpha$-disk with an adiabatic vertical structure. We compute the emitted spectrum by solving the radiative transfer numerically. The observed spectrum is corrected for relativistic effects assuming a Schwarzschild metric, and we also consider the effect of Comptonization by a surrounding hot corona on the observed spectrum. A realistic disk spectrum with a modest amount of Comptonization can describe the continuum shape nearly as well as the best-fit broken power law. n. This work was supported in part by NASA grant NAGW 830 at the University of Chicago and by NSF grant PHY 91-00283 and NASA grant NAGW 1583 at the University of Illinois. omes impossible. Nonradial mode frequencies behave very

The Generalized Comptonization models (Analytical consideration and Monte-Carlo calculations

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fferently from those of the radial mS1310.tex 644 34 12 4047 5555514277 5334 % Session 13 -- Models or Gas Flows and Spectral Formation
Display presentation, Monday, 30, 1994, 9:20-6:30

[13.10] The Generalized Comptonization models (Analytical consideration and Monte-Carlo calculations

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA)

The theory of spectral formation in thermal X$-$ray sources, where the effects of Comptonization and Klein$-$Nishina corrections are important, is presented. Analytical expressions are obtained for the produced spectrum as a function of such input parameters as the plasma temperature, the optical depth of the plasma cloud and the injected soft photon spectrum. The analytical theory developed here takes into account the dependence of the scattering opacity on the photon energy. It is shown that the plasma temperature as well as the asymptotic rate of photon escape from the plasma cloud determine the shape of the upscattered hard tail in the emergent spectra, even in the case of very small optical depths. The escape distributions of photons are given for any optical depth of the plasma cloud and their asymptotic for very small and large optical depths are examined. The comparison of the new analytical theory with extensive Monte-Carlo calculations are also presented. It is shown that this new generalized approach matches extremely well the Monte-Carlo calculation in very wide ranges of plasma temperature (1$-$500 keV) and plasma cloud optical depths (0.1$-$10). The fits of spectra by the analytical Comptonization model for a large variety of hard X$-$ray sources and determination of the plasma temperature in the region of main energy release in Cyg X$-$1 and the Seyfert galaxy NGC 4151 are discussed. archuk \& Xin-Min Hua} P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA)

The theory of spectral formation in thermal X$-$ray sources, where the effects of Comptonization and Klein$-$Nishina corrections are important, is presented. Analytical expressions are obtained for the produced spectrum as a function of such input parameters as the plasma temperature, the optical depth of the plasma cloud and the injected soft photon spectrum.

SPH Calculations of Comet Shoemaker-Levy-9/Jupiter Impact

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e analytical theory developeS1401.tex 644 34 12 4736 5555513622 5333 % Session 14 -- Comets, Asteroids, Meteoroids
Oral presentation, Monday, 30, 1994, 10:00-11:30

[14.01] SPH Calculations of Comet Shoemaker-Levy-9/Jupiter Impact

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL)

The impact of Comet Shoemaker-Levy 9 has been simulated in 2D axisymmetric geometry and full 3D using the Los Alamos Smooth Particle Hydrodynamics code (SPHINX). The objective of this study is to calculate energy deposition profiles and fireball evolution histories for a range of comet parameters. We hope to use these results to infer comet properties from observations. The modeling proceeds in two phases. In Phase I, the collision of the incoming fragment, or bolide, is calculated, and its kinetic energy profile is differentiated to give an energy deposition profile. The deposition profile is used as input to Phase II (see companion paper by Stellingwerf et al.) in which the fireball evolution is calculated.

Two different bolide densities were simulated, 0.2 $g/cm^{3}$ and 0.92 $g/cm^{3}$. The incoming bolide velocity was 60 km/sec and the impact angle was taken to be 45 degrees. Since the calculation is 2D, this means simply that the bolide's depth in the atmosphere is equal to its distance traveled times the cosine of 45 degrees. The baseline calculation assumed a spherical bolide with a diameter of 1 km. Various physical models were used for the bolide including perfect gas equations of state (eos), more realistic eos's and strength of materials.

The model for the Jupiter atmosphere was a fit to the Orton atmosphere. The eos for the atmosphere for most of the calculations was taken to be a perfect gas with a gamma of 1.2. A sesame tabular eos was also used. Rather than modeling the entire atmosphere, small sections were modeled using blocks of particles with blocks being shuffled in and out as the calculation progressed. Calculations were done with different size sections to test the sensitivity of the results to this procedure.

The results indicate energy deposition for the 0.2 density, 1 km diameter case occurring between 50-200 km. The penetration is seen to increase somewhat as the bolide resolution is improved.

SPH Calculations of Comet Shoemaker-Levy-9/Jupiter Impact

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ently from those of the radial mS1402.tex 644 34 12 3232 5555513642 5324 % Session 14 -- Comets, Asteroids, Meteoroids
Oral presentation, Monday, 30, 1994, 10:00-11:30

[14.02] SPH Calculations of Comet Shoemaker-Levy-9/Jupiter Impact

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL)

Smooth Particle Hydrodynamics computations have been carried out of ``phase 2'' (fireball development and rise) of the Shoemaker-Levy 9 impact on Jupiter. Energy deposition was derived from the computations discussed in the previous abstract. Both 2-dimensional axisymmetric and full 3-dimensional computations will be discussed. A fit to the Orton atmosphere of Jupiter was used for the initial density and temperature structure.

These SPH computations clearly show the rise of the expanding heated region on a timescale of about one minute. Kelvin-Helmholtz instabilities are generated along the shear layer at the outer edge of the rising gas. At the top of the bubble a hot shock propagates into the outer atmosphere to heights exceeding 400 km, and should be visible from earth. The temperature of this shock approaches 1 eV for the larger fragments, which should trigger emission by the ionized hydrogen.

Parameter studies of the dependence of observables on fragment mass and density are underway and will be reported.

This work and that of the preceding talk are supported by the Department of Energy.

e used for the bolide including perfect gas equations of state (eos), more realistic eos's and strength of materials. The model for the Jupiter atmosphere was a fit to the Orton atmosphere. The eos for the atmosphere for most of the calculations was taken to be a perfect gas with a gamma of 1.2. A sesame tabular

Heliospheric Current Sheet (HCS) Crossings and Disconnection Events (DEs) in Comet Halley 1985-1986

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s was also used. Rather than modeling thS1403.tex 644 34 12 4402 5555513467 5332 % Session 14 -- Comets, Asteroids, Meteoroids
Oral presentation, Monday, 30, 1994, 10:00-11:30

[14.03] Heliospheric Current Sheet (HCS) Crossings and Disconnection Events (DEs) in Comet Halley 1985-1986

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado)

Evidence is presented for the clear association of HCS crossings with the DEs observed in Halley's comet, 1985-1986. This report ex-tends the pre- vious work (Brandt et al. 1992, BAAS, 24, 1270 and Yi et al. 1994, PASS, in press) from 16 to 19 DEs and is now thought to include all the major DEs observed in comet Halley.

Improvements to the analysis include use of the latest current-sheet loca- tions and a different fitting technique that significantly reduces the uncer- tainties as determined by comparing the extrapolated HCS location with locations directly measured by spacecraft. The RMS dispersion of the spacecraft measurements around the extrap-olated HCS locations is lower than the corresponding value for DEs. These values can be completely reconciled if the DE process (from HCS crossing to actual disconnection) has a dispersion of about 1/2 day.

The comet Halley interval in 1985-1986 was exceptionally favorable for this type of study with excellent imaging coverage of the comet, solar- wind data available from several spacecraft, and HCS loca-tions available for coronal source surfaces. These favorable circum-stances are unlikely to be repeated anytime in the foreseeable fu-ture.

If we assume that DEs have a common cause and that the DEs ob-served in comet Halley are representative, then the result that they are associated with HCS crossings, and apparently no other prop-erty of the solar wind (such as high-speed streams), gives clear di-rection to theoretical efforts.

ng 400 km, and should be visible from earth. The temperature of this shock approaches 1 eV for the larger fragments, which should trigger emission by the ionized hydrogen. Parameter studies of the dependence of observables on fragment mass and density

Orbital Capture of Meteoroids in Grazing Earth Encounters

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404.tex 644 34 12 4225 5555514044 5326 % Session 14 -- Comets, Asteroids, Meteoroids
Oral presentation, Monday, 30, 1994, 10:00-11:30

[14.04] Orbital Capture of Meteoroids in Grazing Earth Encounters

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL)

Some meteoroids such as the daytime fireball of August 10, 1972 that went over the Western United States and the European fireball of October 12, 1990 grazed the atmosphere of Earth before returning to space (at reduced speed). Others, such as the October, 1992 impactor (a small fragment of which smashed into the back end of a car in New York State), entered the atmosphere in a near grazing angle but plunged deeply enough into the atmosphere to ultimately plunge to ground. We can anticipate there there must be some range of closest-approach distances and velocities such that the meteoroid would be captured into a bound orbit around Earth after its first passage through the atmosphere. Any such captured object must ultimately plunge to ground due to further atmospheric dissipation in subsequent passages unless the gravitational field of the moon or other intervention is able to raise its perigee above the atmosphere after the initial capture. We have used a spherical atmospheric model to integrate the passage of meteoroids in near grazing encounters. We find that the corrider for capture is narrow, and it becomes narrower as the pre-encounter velocity V increases. If V = 5 km/s (velocity prior to gravitational acceleration by Earth), stony meteoroids with closest-approach distances of h = 40 km above the ground are captured into bound orbits if their radii, R, are between 3 and 9 meters. For V = 15 km/s and h = 40 km, capture only occurs if R is between 1.5 and 2 meters. Irons with V = 5 km/s and h = 40 km are captured if R is between 1 and 3.5 meters, while irons with V = 15 km/s are captured if R is between 0.6 and 0.9 meters. lations were done with different size sections to test the sensitivity of the results to this procedure. The results indicate energy deposition for the 0.2 density, 1 km diameter case occurring between 50-200 km. The penetration is seen to increase somewhat as the bolide resolution is improved.

The Origin of the Trojan Asteriods?

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ently from those of the radial mS1405.tex 644 34 12 3706 5555512543 5334 % Session 14 -- Comets, Asteroids, Meteoroids
Oral presentation, Monday, 30, 1994, 10:00-11:30

[14.05] The Origin of the Trojan Asteriods?

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB)

The origin of Trojan asteroids, which librate about Jupiter's L$_4$ and L$_5$ points, presents a long-standing puzzle in planetary dynamics. Models of Trojan asteroid origin are usually based on the assumption that they were inserted into their present orbits as a result of collisions after the formation of Jupiter. However, Peale (1994, {\it Icarus} 106 , 308) has shown that the Lagrange points could be stable in the presence of the solar nebula, opening up the possibility that nebula gas drag played a role in inserting asteroids into the Lagrange points. We have recently performed a series of numerical simulations of the migration of planetesimals due to nebula drag. We find that a planetesimal can have a close encounter with a planet which inserts it into the 1/1 resonance. When the planet is on a circular orbit, the planetesimal has a second encounter which causes it to be ejected from the resonance. However, when the planet's orbit is eccentric then the resulting asymmetry in the planetesimal's orbital evolution prevents further close encounters with the planet. In the case of planetesimals approaching a $10^{-6}$M$_{\sun}$ planet with an eccentricity $e \ge 0.02$, then $\sim 10\%$ of the migrating bodies can be thrown into the 1/1 resonance and decay down to the L$_5$ point.

This work was supported in part through NASA Planetary Geology and Geophysics Grant \# NAGW-2061 at UCSB and \# NAGW-1107 at SUNYSB.

nd 2 meters. Irons with V = 5 km/s and

The Record-Shattering Gamma Ray Burst of February 17 1994

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= 40 km are captS1501.tex 644 34 12 4014 5555513346 5324 % Session 15 -- Gamma Ray Bursts
Oral presentation, Monday, 30, 1994, 10:00-11:30

[15.01] The Record-Shattering Gamma Ray Burst of February 17 1994

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman)

A gamma-ray burst which occurred on February 17 1994 was observed by Ulysses, BATSE, COMPTEL, and EGRET. Using Ulysses and BATSE, an annulus of arrival positions with a width of about 5' was obtained which is consistent with all other position determinations. Of particular interest is the EGRET observation of this event. During the 160 second period when the burst was clearly observed by Ulysses and BATSE, EGRET detected 10 photons with energies up to 4.4 GeV. In the 15 minutes which followed, 6 photons were detected. The diffuse gamma ray background in this direction results in about one photon above 30 MeV detected by EGRET in 7 minutes. On the subsequent Compton Observatory orbit, 1.5 hours later, EGRET had 20 minutes of livetime, and 10 gamma rays were detected from the region around the annulus, one with energy 26 GeV. This represents both the longest lasting and the highest energy emission ever observed from a gamma-ray burst source. tion prevents further close encounters with the planet. In the case of planetesimals approaching a $10^{-6}$M$_{\sun}$ planet with an eccentricity $e \ge 0.02$, then $\sim 10\%$ of the migrating bodies can be thrown into the 1/1 resonance and decay down to the L$_5$ point. This work was supported in part through NASA Planetary Geology and Geophysics Grant \# NAGW-2061 at UCSB and \# NAGW-1107 at SUNYSB. nd 2 meters. Irons with V = 5 km/s and

The Spatial Coincidence of Two COMPTEL Gamma Ray Bursts: GRB930704 and GRB940301

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= 40 km are captS1502.tex 644 34 12 3542 5555513606 5331 % Session 15 -- Gamma Ray Bursts
Oral presentation, Monday, 30, 1994, 10:00-11:30

[15.02] The Spatial Coincidence of Two COMPTEL Gamma Ray Bursts: GRB930704 and GRB940301

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.)

We report on the spatial coincidence of two gamma ray bursts imaged by the COMPTEL experiment on the Compton Gamma Ray Observatory. These bursts, GRB930704 and GRB940301 out of a total of seventeen, are separated by $1.7\deg$ ($\sim$1 RMS $\sigma$ for these two bursts). They potentially arise from the same object, placing severe constraints on the cosmological origin of these events. Assuming gamma ray bursts are distributed isotropically and taking into account the COMPTEL sky exposure map, the probability of two random bursts occuring within $1.7\deg$ is less than 5\%. The lightcurves and spectra of the two bursts measured in both the telescope and spectroscopic modes differ significantly, ruling out the possibility that the two bursts are gravitationally lensed images of the same object. With the COMPTEL rate of burst detections within its field-of-view and assuming that this is a chance coincidence of independent events, another similar coincidence of bursts should not occur in another 50 years of COMPTEL operation. Geophysics Grant \# NAGW-2061 at UCSB and \# NAGW-1107 at SUNYSB. nd 2 meters. Irons with V = 5 km/s and

Constraints on the Luminosity Function of Gamma--Ray Bursts Detected by BATSE

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= 40 km are captS1503.tex 644 34 12 2407 5555512255 5330 % Session 15 -- Gamma Ray Bursts
Oral presentation, Monday, 30, 1994, 10:00-11:30

[15.03] Constraints on the Luminosity Function of Gamma--Ray Bursts Detected by BATSE

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH)

We have utilized the BATSE--measured gamma--ray burst intensity distribution in conjunction with the general properties satisfied by integral moments to constrain significantly the permissable range of luminosities from which the observed gamma--ray bursts must be drawn. The constraints are independent of the functional form of the burst radial distribution. Given a distance independent luminosity function, the range of luminosity from which 80$\%$ of the observed gamma--ray bursts must be drawn may not exceed $\sim$6.5, with a 3--sigma upper limit of approximately 12. The finding that a substantial majority of bursts are passable standard--candles has important ramifications for many burst production models. the COMPTEL sky exposure map, the probability of two random bursts occuring within $1.7\deg$ is less than 5\%. The lightcurves and spectra of the two bursts measured in both the telescope and spectroscopic modes

The Slope of the BATSE logN - Log C

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ffer significantly, ruling out theS1504.tex 644 34 12 1754 5555514273 5337 % Session 15 -- Gamma Ray Bursts
Oral presentation, Monday, 30, 1994, 10:00-11:30

[15.04] The Slope of the BATSE logN - Log C

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University)

I use a smoothed nonparametric method (Caditz \& Petrosian 1993) to determine the slope of the $\log (N)$- $\log (C_p)$ distribution for $\sim 200$ $\gamma$-ray bursts observed by BATSE. This method reduces uncertainties due to detector threshold variation and numerical fluctuations and it has the advantage of determining the slope directly from the data without binning or parametric fits. The results are compared with halo and cosmological models for the intrinsic burster distribution.

Further Constraints on Galactic Coronal Models of BATSE Gamma-Ray Bursts: (1) Limits on Local Group Member Contributions, and (2) Implications for Spiral Arm Plus Coronal Distributions

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mma--ray bursts muS1505.tex 644 34 12 4024 5555512274 5330 % Session 15 -- Gamma Ray Bursts
Oral presentation, Monday, 30, 1994, 10:00-11:30

[15.05] Further Constraints on Galactic Coronal Models of BATSE Gamma-Ray Bursts: (1) Limits on Local Group Member Contributions, and (2) Implications for Spiral Arm Plus Coronal Distributions

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH)

distributions and luminosity functions are analyzed and compared to BATSE observations using techniques described in Hakkila et al. (1994a, ApJ 422, 664) and Hakkila et al. (1994b, Proc. 1993 Hunts. Workshop). Local Group Galaxies other than the Milky Way and M31 do not appear able to contribute significantly in any coronal/extended halo scenario, as they would (1) raise the overall of the sample, and (2) show up in the two-point angular correlation function. Also, Galactic spiral arm/disk populations have been combined with coronal/extended halo populations to determine the extent to which they can be added without severely affecting sample isotropy. The models favor very low-luminosity spiral arm bursts (those that are so close that no spiral structure is noticeable) and/or small observed numbers of such bursts (less than 20% of the BATSE sample), while simultaneously constraining the spatial and luminosity properties of the coronal/extended halo population. This work has been supported by NASA grants NAG8-192 and NRA 92-OSSA-17.

1 and 3.5 meters, while irons with V = 15 km/s are captured if R is between 0.6 and 0.9 meters. lations were done with different size sections to test the sensitivity of the results to this procedure. The results indicate energy deposition for the 0.2 density, 1 km diameter case occurring between 50-200 km. The penetration is seen to increase somewhat as the bolide resolution is improved.

Gamma-Ray Bursts and Large-Scale Anisotropy

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ently from those of the radial mS1506.tex 644 34 12 4571 5555513753 5343 % Session 15 -- Gamma Ray Bursts
Oral presentation, Monday, 30, 1994, 10:00-11:30

[15.06] Gamma-Ray Bursts and Large-Scale Anisotropy

Gamma-Ray Bursts and Large-Scale Anisotropy

Previous abstract Next abstract

ently from those of the radial mS1506.tex 644 34 12 4571 5555513753 5343 % Session 15 -- Gamma Ray Bursts
Oral presentation, Monday, 30, 1994, 10:00-11:30

[15.06] Gamma-Ray Bursts and Large-Scale Anisotropy

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.)

We show that the brightest $\approx$ 20 sources in the current BATSE catalog (as measured by the peak rates in 64, 256 and 1024 ms and the four fluences) are not distributed isotropically on the sky and that their mean vector points in a direction near several known indicators of large-scale structure within $z \sim 0.5$. These structure indicators include peaks in the distributions of low redshifts quasars, optical galaxies, IRAS galaxies, and the microwave background dipole moment. The mean vector of the large-scale structure indicators is centered on galactic coordinates $l = 265\deg$ and $b = 40\deg$ and the mean vector of the brightest $\gamma$-ray bursts is centered on $l = 256\deg$ and $b = 42\deg$. (The close agreement is at least in part accidental since the standard error of the means are somewhat greater than the angular separation of the two mean vectors). The statistical significance of the anisotropy itself is, as expected, only marginal with the probability of a chance occurrence being $\sim 0.01 - 0.1$. However, when combined with the probability of an accidental correlation ($\sim$ 0.1) with the large-scale indicators, a physical association is suggested. If real, the absence of a similar correlation in the PVO, Kronus and earlier $\gamma$-ray burst data, which detected the rarer and much brighter homogeneously distributed bursts, would imply that these instruments primarily detected a different population of sources, a possibility already suggested by the absence of cyclotron lines in the BATSE bursts and the different flux distributions. As a test of these speculative results we predict that the mean vector of the $\sim 10\%$ brightest bursts in future BATSE catalogs will point in a direction near to that found here.

n is seen to increase somewhat as the bolide resolution is improved.

Compatibility of the BATSE Gamma-Ray Burst Data with General Friedmann Cosmological Models

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ently from those of the radial mS1507.tex 644 34 12 3363 5555512261 5333 % Session 15 -- Gamma Ray Bursts
Oral presentation, Monday, 30, 1994, 10:00-11:30

[15.07] Compatibility of the BATSE Gamma-Ray Burst Data with General Friedmann Cosmological Models

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC)

We have used a technique based on analysis of normalized integral moments to test the compatibility of various Friedmann cosmological models (including those which admit a cosmological constant $\Lambda$) with the intensity distribution of gamma--ray bursts observed by BATSE. We find that models with a zero $\Lambda$ and a (typical) spectral index $\alpha$ = 2 are consistent with the data only if the maximum redshift observed by BATSE is less than 1.25. Higher limiting redshifts are possible only if the bursts have a spectrum much flatter than typically observed, or if they are embedded in a Universe with a positive $\Lambda$. Furthermore, the closer the actual value of the maximum redshift to the limiting values derived, the narrower must be the width of the luminosity distribution function for the bursts. Coupled with a similar result for Euclidean geometries (see the paper by Horack and Emslie elsewhere at this meeting), this result requires that if gamma--ray bursts truly span a wide range of burst luminosities, then they must not only be cosmological in origin, but also must be embedded in a Universe with a positive cosmological constant.

ddress{Department of Physics \\ UAH \\

Compatibility of the BATSE Gamma-Ray Burst Data with General Friedmann Cosmological Models

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ently from those of the radial mS1507.tex 644 34 12 3363 5555512261 5333 % Session 15 -- Gamma Ray Bursts
Oral presentation, Monday, 30, 1994, 10:00-11:30

[15.07] Compatibility of the BATSE Gamma-Ray Burst Data with General Friedmann Cosmological Models

Filamentary Structure in Orion and Monoceros Molecular Clouds

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ffilS1601.tex 644 34 12 3534 5555514035 5327 % Session 16 -- Molecular Clouds, Star Formation, Very Young Stars, T Tauri Stars
Oral presentation, Monday, 30, 1994, 10:00-11:30

[16.01] Filamentary Structure in Orion and Monoceros Molecular Clouds

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky)

The filamentary structure in 13CO radio maps of the Orion A, Orion B and Monoceros R2 molecular clouds was analyzed using the Minimal Spanning Tree. This represents the first time the MST has been applied to an extended region such as maps of molecular clouds. The method of preparing and analyzing the data is presented. Integrated maps over a range of velocities were examined as well as a velocity cube constructed from individual 0.5 km s-1 wide channel maps. The results show that there is overwhelming objective and statistical evidence that the filamentary structure does exist in all three of these regions. Previous techniques to identify filaments were generally visual, and therefore subjective. The major filaments in Orion A show linear features extending throughout the entire length. The structure in the velocity cube clearly shows the continuous velocity gradient. Orion B cloud shows distinct regions with north to south orientations. The velocity cube contains a number of filaments at greatly differing velocities, with little evidence of large scale velocity gradients. Mon R2 cloud exhibits two main filamentary components, one of which is associated with both bright condensed regions. The velocity structure reveals an overall velocity gradient. d earlier $\gamma$-ray burst data, which detected the rarer and much brighter homogeneously distributed bursts, would imply that these instruments

KWIC Observations of the Orion Nebula

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imarily detecteS1602.tex 644 34 12 3753 5555513765 5344 % Session 16 -- Molecular Clouds, Star Formation, Very Young Stars, T Tauri Stars
Oral presentation, Monday, 30, 1994, 10:00-11:30

[16.02] KWIC Observations of the Orion Nebula

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University)

spectrometer, KWIC on the Kuiper Airborne Observatory. KWIC (Kuiper Widefield Infrared Camera) is an imaging spectrometer/spectrophotometer designed to yield diffraction limited images between 18 and 44 microns from the KAO. KWIC centers on a SIRTF funded 128 by 128 pixel Si:Sb BIB array. The plate scale (2.5" per pixel) was chosen to oversample the primary diffraction lobe of the KAO telescope at 35 microns (9"). Even with this oversampling the large array format yields a 5.4 by 5.4 arcminute field of view. The resolution achieving devices are fully tunable cryogenic Fabry-Perot interferometers.

We flew KWIC on the KAO for the first time in late February, 1994. For this paper, we will discuss the large scale (7' by 11') image we obtained of the Orion Nebula in the 37 micron continuum. The 37 micron continuum traces UV heated warm dust at the HII region/molecular cloud interface or near the IR cluster. Our diffraction limited image breaks the Orion bar interface region into wispy, clumpy structures, defines the bowl-shaped edges of the blister HII region, shows finger-like projections of dust away from the Orion outflow and point-like sources near the Trapezium cluster. Our data will be tied in with other tracers to constrain the physical conditions and morphology of the Orion Nebula.

nts

Polarization Imaging of Star Formation Regions with the OVRO MM Array

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imarily detecteS1603.tex 644 34 12 3733 5555514052 5331 % Session 16 -- Molecular Clouds, Star Formation, Very Young Stars, T Tauri Stars
Oral presentation, Monday, 30, 1994, 10:00-11:30

[16.03] Polarization Imaging of Star Formation Regions with the OVRO MM Array

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech)

We report on an ongoing project to measure with high resolution the magnetic field geometries in deeply embedded star forming regions. It is widely believed that magnetic fields play a crucial role in star formation on scales ranging from the stellar size to that of the parent molecular cloud. So far, measurements of the magnetic field structure have only been made on the largest scales and little is known about the structure within collapsing protostellar condensations and circumstellar disks. Interferometric imaging of linearly polarized emission from magnetically aligned dust grains can provide information on the magnetic geometry in nearby star forming regions on scales ranging from 100 to 3000 A.U.

In 1994 February we installed tunable reflecting polarizers on 5 elements of the OVRO mm interferometer. Configured as $\lambda/4$ plates the polarizers allow us to multiplex between right and left hand circular polarizations on each telescope and thus to make images using all 4 stokes parameters. Cross circular polarizations minimize the systematic errors in measuring weakly linearly polarized emission such as that expected from aligned dust grains in star forming regions.

We will present a summary of the instrument performance and results from the ongoing polarimetric observations of dust and maser emission from nearby star forming regions.

nts

Submillimeter Observations of $\rm \bf H_2{}^{18}O$ in Molecular Clouds

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imarily detecteS1604.tex 644 34 12 4445 5555512510 5330 % Session 16 -- Molecular Clouds, Star Formation, Very Young Stars, T Tauri Stars
Oral presentation, Monday, 30, 1994, 10:00-11:30

[16.04] Submillimeter Observations of $\rm \bf H_2{}^{18}O$ in Molecular Clouds

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech)

Although water may be abundant in molecular clouds, measurements of the abundance are difficult because atmospheric absorption prevents access to transitions between low-lying levels. Highly excited transitions are observable from the ground, but they sample only hot and dense gas and are usually masing, and are not useful for deriving the abundance. We have detected the 547~GHz $1_{10} - 1_{01}$ ground-state transition of ortho-$\rm H_2{}^{18}O$, using our submillimeter SIS receiver flying aboard the NASA Kuiper Airborne Observatory. The 547~GHz line is in absorption towards Sgr~B2 and is in emission in OMC-1. For Sgr~B2, the source structure and radiative transfer modeling lead us to conclude that we are sampling the cool, quiescent molecular envelope rather than the hot core region. For ortho-$\rm H_2{}^{18}O$, only the $1_{01}$ ground state is expected to have a significant population in this envelope. We derive an $\rm H_2{}^{18}O$ column density of $1.1 \times 10^{14} \ \rm cm^{-2}$, which gives $\rm H_2{}^{18}O / H_2 \approx 7 \times 10^{-10}$ and $\rm H_2O / H_2 \approx 1.8 \times 10^{-7}$, assuming $\rm {}^{16}O / {}^{18}O \approx 250$. The velocity width of the 547~GHz emission line in OMC-1 is consistent with the $\rm 20\ km\ s^{-1}$ outflow which is associated with 22~GHz maser emission, indicating that we may be sampling shock-excited gas. We have also made a tentative detection in OMC-1 of the $2_{11}-2_{02}$ transition of para-$\rm H_2{}^{18}O$ at 745~GHz. This work was supported in part by grants from NASA (NAG2-744 and NAGW-107), NASA/JPL, and an NSF Presidential Young Investigator grant to J. Zmuidzinas.

will point in a direction near to that found here. n is seen to increase somewhat as the bolide resolution is improved.

Modeling the Infrared Spectra of Dark Globules: Effect of Transiently Heated Small Grains

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ently from those of the radial mS1605.tex 644 34 12 5205 5555512423 5327 % Session 16 -- Molecular Clouds, Star Formation, Very Young Stars, T Tauri Stars
Oral presentation, Monday, 30, 1994, 10:00-11:30

[16.05] Modeling the Infrared Spectra of Dark Globules: Effect of Transiently Heated Small Grains

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech)

Isolated dark globules, also known as Bok globules or Barnard objects, are nearby dense interstellar clouds of dust and gas which are primarily heated externally by the interstellar radiation field (ISRF). Many dark globules show an excess in the mid-infrared (MIR; $10 - 100 \mu m$). This excess has generally been attributed to an internal heat source (e.g., a protostellar object), since conventional large grains heated only by the ISRF cannot account for the MIR excess. On the other hand, if very small grains are present in these clouds, they may be responsible for the MIR excess through transient heating by the ISRF. In such a case, the postulation of an internal heat source is not necessary.

To quantitatively determine whether a MIR excess in dark globules uniquely implies the presence of an internal heat source, we have modeled B335 - a source known to have a $60 \mu m$ excess and an internal heat source. We have compared observational data with the results of two models: an internally heated one with only conventional large grains ($a \sim 0.1 \mu m$), and an externally heated one with both large and very small grains ($a > 10 \AA$). We find that both models can reproduce the observed flux spectrum, implying that a MIR excess in dark globules does not uniquely imply the presence of an internal heat source. The parameters for both models are within observational constraints.

We also find that although the flux may be used to differentiate between these two cases, the surface brightness is a more important diagnostic tool. Internally heated sources show extra emission at the center, and strong short wavelength emission at smaller radii. Externally heated sources, on the other hand, show less emission at the center of the cloud, and limb brightening at shorter wavelengths. Our models suggest that these two possibilities could be differentiated at $ 60 \mu m$.

This work has been partially supported by a NASA Grant to CML, and an NDSEG/DoD Fellowship to SDD.

modes and the NB/FB quasi-periodic intensity oscillations found in LMXBs, which also display striking frequency stability.

WFPC-2 Observations of the Circumstellar Nebulosity of T Tau and HL Tau

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S1606.tex 644 34 12 4656 5555514123 5340 % Session 16 -- Molecular Clouds, Star Formation, Very Young Stars, T Tauri Stars
Oral presentation, Monday, 30, 1994, 10:00-11:30

[16.06] WFPC-2 Observations of the Circumstellar Nebulosity of T Tau and HL Tau

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech)

T Tauri lies on an arc of reflection nebulosity which extends approximately 3$^{\prime\prime}$ N and 2$^{\prime\prime}$ SW from the star. This nebula has a characteristic width of 0.5$^{\prime\prime}$, is concave open toward the nearby Burnham's Nebula, and is closely aligned with the optical polarization vector of the system. The morphology T Tau's edge-brightened cometary nebula is similar to models of scattered light from a flared, optically thick disk observed from 45 degrees above the equator plane. No optical counterpart to the infrared companion is seen to a limiting magnitude of V= 23.

WFPC2 images of HL Tauri show that this object is entirely reflection nebulosity at optical wavelengths. No stellar source is visible to a limiting magnitude of V$=$ 26, a result which dictates a significant upward revision of the luminosity and mass estimates for HL Tau. The V-I color of the nebula is dominated by foreground extinction, with only small internal color changes. The bright core of the nebula has an east-west elongation of 1$^{\prime\prime}$ and has an unusual morphology. We will discuss the implications of these results for i). HL Tau's stellar type and ii). models for the distribution of the circumstellar matter. esence of an internal heat source, we have modeled B335 - a source

10 micron Spectroscopy of 51 Ophiuchi

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own to have aS1607.tex 644 34 12 2561 5555514424 5336 % Session 16 -- Molecular Clouds, Star Formation, Very Young Stars, T Tauri Stars
Oral presentation, Monday, 30, 1994, 10:00-11:30

[16.07] 10 micron Spectroscopy of 51 Ophiuchi

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC)

We report thermal infrared spectroscopy of 51 Ophiuchi (B9.5Ve) obtained in Feb 1993 at the IRTF using the Aerospace 3 - 14 micron spectrograph. The IR excess reported by Fajardo et al. (ApJ Let, 417, L33) is resolved to show a broad silicate emission feature that would seem to be associated with warm (600 K), small dust particles. The feature is smooth and nearly structureless and does not show the breaks in the spectrum near 9 and 11.3 microns. In this paper we present the spectrum and discuss it in relation to those of beta Pic, other shell sources and some recent comets. of the circumstellar matter. esence of an internal heat source, we have modeled B335 - a source

Spatially Resolved Spectroscopy of Close Infrared Binary Companions

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own to have aS1608.tex 644 34 12 2723 5555513602 5334 % Session 16 -- Molecular Clouds, Star Formation, Very Young Stars, T Tauri Stars
Oral presentation, Monday, 30, 1994, 10:00-11:30

[16.08] Spatially Resolved Spectroscopy of Close Infrared Binary Companions

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg)

We present initial results from our program of near infrared spectroscopy of close binary pre-main sequence stars. This study concentrates on the so-called Infrared Companions (IRC). These objects have colour temperatures lower than any known star ($< 1500$~K), yet are frequently more luminous than their visible primaries. Matter accreting onto the companion or perhaps a circumstellar disk is one possible explanation for the large infrared emission from IRC's. By spatially separating the primary and companion, the spectra allow us to search for signatures of accretion shocks and disks, for example molecular hydrogen and CO emission in the K band (2.0--2.4~$\mu$m). We show and discuss the spectra of several IRC systems, including T~Tau, Haro~6--10, and UY~Aur.

have modeled B335 - a source

ISO-NASA Key Project: The Birth and Death of Planetary Systems

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own to have aS1609.tex 644 34 12 4346 5555513002 5332 % Session 16 -- Molecular Clouds, Star Formation, Very Young Stars, T Tauri Stars
Oral presentation, Monday, 30, 1994, 10:00-11:30

[16.09] ISO-NASA Key Project: The Birth and Death of Planetary Systems

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College)

The aim of this Infrared Space Observatory [ISO], NASA-selected Guarranteed Time observing program is to establish the true frequency for far-infrared excesses in a volume-limited sample of main sequence and related stars, in order to address the relative success or failure of single stars in processes related to the forming of planetary systems. For a volume-limited subset of main sequence and related stars, PHT03 measurements at 3.6, 11.5, 20 and 60 microns will be obtained, using a 120 arcsec aperture in all cases to eliminate possible companion confusion with differing apertures. For the M dwarfs, 100 micron observations will also be obtained. For some, brighter sources, more extensive wavelength coverage and improved spatial resolution will be attempted, using CAM and SWS. We also plan PHOT micro-scanning 60 micron observations of the brightest and nearest Vega-like sources to measure the characteristic sizes of the emitting regions and obtain some information regarding their shapes and orientations. The goal is to derive the intrinsic size and shape of the FWHM contour of the emitting region. We also plan photometry of selected lines of sight through the zodiacal dust into possible outer solar system (Kuiper Belt) material. Observations at a range of wavelengths, ecliptic latitudes and at 2 epochs are designed to help untangle foreground from background flux, not necessarily to look for individual macroscopic objects. We are pleased to acknowledge partial support for this effort through NASA grant NAGW-3680 to the University of Denver.

E.Stencel} % REQUIRED

Multi-waveband Observations of Flat Radio Spectrum Quasars

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itle{ISO-NASA Key Project: The BirthS1701.tex 644 34 12 5574 5555512265 5341 % Session 17 -- Radio Galaxies and High Luminosity AGNs
Oral presentation, Monday, 30, 1994, 10:00-11:30

[17.01] Multi-waveband Observations of Flat Radio Spectrum Quasars

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion)

Multi-waveband observations of thirty quasars and active galaxies with flat radio spectra (referred to here as FRSQ's) have been conducted to determine their radio to infrared and X-ray to gamma-ray properties and the relationships between them. Specifically, the synchrotron self-Compton (SSC) process is examined as a likely common radiation mechanism. Very Long Baseline Interferometry is used in conjunction with radio to submillimeter-wave observations to determine the parameters of the synchrotron spectrum. These parameters are used to predict the SSC X-ray flux densities. Seven of thirty sources have predicted Compton X-ray flux densities well above the observed flux densities obtained with the ROSAT satellite. It is concluded that these sources experience internal relativistic motion directed toward the observer's line of sight, which lowers the predicted Compton X-ray flux. Three of these seven sources are detected at gamma-ray frequencies. Model spectra show that the X-rays are consistent with the first order SSC process. The gamma-rays are not produced via second order self-Compton scattering, but are rather produced either by first order self-Compton scattering or by another process. A comparison of the ROSAT X-ray flux densities and those obtained earlier with the Einstein Observatory show that many FRSQ's are X-ray variables, with a factor of 2--3 between minimum and maximum brightness. Sources that were observed more than once with ROSAT also show variability over this shorter timescale. In several sources (e.g., 4C 39.25 and NRAO 140) the X-ray variability is associated with millimeter variability. Gamma-ray detections are also related to increases in the radio to millimeter-wave spectrum. Model spectra show that the relationship between the predicted high energy and radio to infrared spectra is sensitive to whether magnetic field or electron energy density dominates the variations. Implications for the SSC model and models that include scattering of external photons are discussed. Statistical analysis shows that the millimeter-wave and X-ray luminosities for the sample are strongly correlated, with a linear regression slope $\sim$ 0.6. The peak in the distribution of X-ray to millimeter spectral indices also indicates a strong connection between millimeter-wave and X-ray emission.

Radio Galaxies in Abell Rich Clusters

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S1702.tex 644 34 12 4616 5555513230 5327 % Session 17 -- Radio Galaxies and High Luminosity AGNs
Oral presentation, Monday, 30, 1994, 10:00-11:30

[17.02] Radio Galaxies in Abell Rich Clusters

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU)

We have defined a complete sample of radio galaxies chosen from Abell's northern catalog consisting of all clusters with measured redshifts $< 0.09$. This sample consists of nearly 300 clusters. A multiwavelength survey including optical CCD R-Band imaging, optical spectroscopy, and VLA 20 cm radio maps has been compiled. I have used this database to study the optical/radio properties of radio galaxies in the cluster environment. In particular, optical properties have been compared to a radio-quiet selected sample to look for optical signatures which may distinguish radio galaxies from normal radio-quiet ellipticals. The correlations between radio morphology and galaxy type, the optical dependence of the {\sl FR I/II} break, and the univariate and bivariate luminosity functions have been examined for this sample. This study is aimed at understanding radio galaxies as a population and examining their status in the AGN heirarchy. The results of this work will be applied to models of radio source evolution.

The results from the optical data analysis suggest that radio galaxies, as a class, cannot be distinguished from non-radio selected elliptical galaxies. The magnitude/size relationship, the surface-brightness profiles, the fundamental plane, and the intrinsic shape of the radio galaxies are consistent between our radio galaxy and control sample. The radio galaxies also trace the elliptical galaxy optical luminosity function in clusters very well; with many more $L^*$ galaxies than brightest cluster members. Combined with the results of the spectroscopy, the data are consistent with the idea that all elliptical galaxies may at some point in their lifetimes become radio sources.

In conclusion, I present a new observational picture for radio galaxies and discuss the important properties which may determine the evolution of individual sources.

d or electron energy density dominates the variations. Implications for the SSC model and models that include

High Redshift Radio Galaxies

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atS1703.tex 644 34 12 1660 5555513567 5341 % Session 17 -- Radio Galaxies and High Luminosity AGNs
Oral presentation, Monday, 30, 1994, 10:00-11:30

[17.03] High Redshift Radio Galaxies

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA)

High redshift radio galaxies appear to be young systems rich in gas and dust and undergoing substantial star formation. The also radiate a substantial amount of reprocessed light from an active nucleus. At redshifts $z>2$, these massive galaxies are the best observational probes of ongoing galaxy formation at early epochs. Recent results from deep optical, infrared, submillimeter, and radio observations will be presented.

uthor{K. C. Chambers} P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA)

A comparison between the rest-frame optical/UV continua of high ($z\ge3$) and low ($z\sim0.1$) redshift quasars

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gh redshift radio galaxiesS1704.tex 644 34 12 5500 5555513246 5331 % Session 17 -- Radio Galaxies and High Luminosity AGNs
Oral presentation, Monday, 30, 1994, 10:00-11:30

[17.04] A comparison between the rest-frame optical/UV continua of high ($z\ge3$) and low ($z\sim0.1$) redshift quasars

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO)

The evolution of the optical quasar luminosity function is well described as `pure luminosity evolution' with the characteristic luminosity, $L_{*}$, $\propto (1+z)^{k}$ ($k\sim3$ for $z<\sim2$ and $k\sim0-1$ for $z>\sim2$; e.g. Boyle et al. 1991, in ``The Space Distribution of Quasars, ed D. Crampton; Hewett et al. 1993, ApJ, 406 L43). In an effort to relate the statistical to physical evolution for quasars and, thus, constrain models for the quasar energy source, we have collected IR and optical data for $z\ge3$ and $z\sim1$ quasars selected to represent equally well all those at a given epoch (i.e. $L/L_{*}$ within a fixed range). From these data, we have constructed optical/UV continua, and we compare these to the mean continuum for a set of 47 $z\sim0.1$ quasars (Elvis et al. 1994, ApJS, submitted).

For the bright, $z=3.02$ quasar, HS1946+7658 (Hagen et al. 1992, AA 253, L5), we have obtained 5GHz and 1415MHz data from the VLA, an upper limit at N (10.6$\mu$m), near-IR photometry and spectroscopy, optical spectrophotometry and high resolution (FWHM $\sim80$ km s$^{-1}$) spectra, and a ROSAT PSPC spectrum. The spectral energy distribution (SED) of HS1946+7658 appears generally similar to the mean $z\sim0.1$ continuum, however it differs within specific spectral regions. In the UV, after correcting for reddening and flux suppression due to the Ly$\alpha$ `forest', we find that the continuum turns down more rapidly than the mean $z\sim0.1$ SED. Absorption by numerous low column density line-of-sight clouds might produce this residual turnover (Press and Rybicki 1993, ApJ, 418, 585). At $\lambda_{rest} \sim 3000$\AA, the SED of HS1946+7658 shows little evidence for the blended FeII and Balmer continuum emission which is common to the spectra of low $z$ quasars, and thus suggests a lack of FeII. Finally, our upper limit at N ($\lambda_{rest} \approx 2.5\mu$m), indicates that HS1946+7658 is not redder than the average low $z$ quasar as would be expected if it were recently formed in a dusty galaxy merger (Sanders et al. 1988, ApJ, 325, 74).

er-wave and X-ray emission.

Simultaneous Visible and Near-Infrared Photometry of OJ287 During the December 1993 Flare.

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S1705.tex 644 34 12 3322 5555513107 5326 % Session 17 -- Radio Galaxies and High Luminosity AGNs
Oral presentation, Monday, 30, 1994, 10:00-11:30

[17.05] Simultaneous Visible and Near-Infrared Photometry of OJ287 During the December 1993 Flare.

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias)

We present visible and near infrared observations of the blazar OJ287 taken during a flare of nearly two magnitudes amplitude in V, which peaked on December 6th 1993 at V=14.5 (Kidger et al., 1993, IAUC 5909). Simultaneous visible (BVRI) and near infrared (JHK) photometry were taken on two nights during the decline phase of this outburst. The observations reveal considerable variations in the level of activity during the flare: at maximum very rapid variations were seen (several tens of percent in less than half a hour); whilst a very low amplitude of variation was generally observed pre- and post-maximum.

Our data show significant variations in the colours and hence spectral slope in the infrared on timescales of hours, but very little variability in the visible, suggesting a high frequency cut-off in the variations of the continuum spectral slope at close to 1 micron. The size and time scale of the variations are inconsistent with a shocked-jet model and require highly variable synchrotron emission from small regions of the accretion disc. ear-IR photometry and spectroscopy, optical spectrophotometry and high resolution (FWHM $\sim80$ km s$^{-1}$) spectra, and a ROSAT PSPC spectrum. The spectral energy distribution (SED) of HS1946+7658 appears generally similar to the mean

X-ray and Ultraviolet Absorbing Outflows In Quasars

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\sim0.1$ continuum, however it differs within specific spectrS1706.tex 644 34 12 4427 5555512752 5343 % Session 17 -- Radio Galaxies and High Luminosity AGNs
Oral presentation, Monday, 30, 1994, 10:00-11:30

[17.06] X-ray and Ultraviolet Absorbing Outflows In Quasars

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO)

\def\etal {et~al. } \def\lax {${_<\atop^{\sim}}$} \def\gax {${_>\atop^{\sim}}$}

We will present new results on absorbing outflows in quasars 3C351 (Mathur \etal~ 1994) and 3C212 (Mathur 1994). We have shown that the X-ray and UV absorption observed in these quasars' spectra is due to the same material. This new discovery enables us to constrain the physical characteristics of the absorbing material through the combined X-ray and UV analysis. In 3C351 the absorber is found to be outflowing (v $\sim 2000 km~s^{-1}$), highly ionized (U = 6--12), has large column density ($N_H =$ 1 -- 2 $\times 10^{22} cm^{-2}$), is situated outside the broad emission line region (R $> 1/3 ~pc.$), and has low density (n \lax $10^7 cm^{-3}$). The corresponding mass loss rate is $0.05<$ \.{M} $< 5 ~M_{\odot} ~yr^{-1}$ for covering factors between 1\% and unity. The radiation pressure experienced by the ionized absorber is easily sufficient to accelerate it to outflow velocities of a few thousand km s$^{-1}$. These properties describe a component of nuclear material not previously recognized.

In 3C212 the absorber is again required to be partially ionized and the low energy X-ray absorption is caused by residual metal opacity. Normally X-ray absorbers are assumed to be neutral unless a recovery of the X-ray spectrum is seen at low energies. The identification of the X-ray absorber with the UV absorber in 3C212 demonstrates a new method to identify ionized X-ray absorbers even when the X-ray data itself is inadequate.

We now suspect that many more cases of ionized absorbers will be identified in this way and that the large number of derivable physical parameters will allow us to understand the origin of this material and its role in active galactic nuclei. ons in the colours and hence spectral slope in the infrared on timescales of hours, but very little variability in the visible, suggesting a high frequency cut-off in the variations of the continuum spectral slope at close

Spectropolarimetric observations of OJ 287 during outburst

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1 microS1707.tex 644 34 12 5133 5555513035 5332 % Session 17 -- Radio Galaxies and High Luminosity AGNs
Oral presentation, Monday, 30, 1994, 10:00-11:30

[17.07] Spectropolarimetric observations of OJ 287 during outburst

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias)

The BL Lac object OJ287 has been studied with the 4.2m William Herschel Telescope (WHT) from the Spanish Observatory of La Palma on six nights in December 1993 and January 1994, as part of the OJ-94 International Campaign of monitoring of OJ287. At the time of the first observations, in mid-December the object was in the decline phase of a moderate outburst, reaching minimum in early January. In order to get both spectral and polarimetric observations, we used the ISIS double spectropolarimeter, giving us a spectral resolution of 3┼ over the range from 5500-9000┼. This permits both the rapid continuum polarisation variations to be examined from individual exposures (resolution 40 minutes, provided by four individual integrations with different positions of the calcite retarder) and , by summing all the exposures of a full night (a total integration time of up to 8 hours), the weak emission lines may be studied at a resolution far higher than has ever previously been possible. A period or pseudoperiod of 11.65 yr has been claimed for the outbursts of this object (Sillapaa et al 1988, Kidger et al 1992), which has been interpreted as due to a binary black hole (Sillapaa et al 1988). This model predicts an outburst at some time in 1994. If the Winter 1993-94 eruption corresponds to the expected 1994 outburst, the rise in brightness would be associated to accretion processes and, therefore, we hope to find a polarized spectrum different of those originated by synchrotron sources. The WHT observations are, we believe, the first of their kind of a blazar and these data will help to elucidate this question, apart from supplying valuable information on the emission processes in active galactic nuclei.

References: Sillanpaa A., Haarala S., Valtonen M., Sundelius B., Byrd G.G, 1988, ApJ, 325, 628 Kidger M., Takalo L., Sillanpaa A., 1992, A&A, 264, 32 mu$m), indicates that HS1946+7658 is not redder than the average low $z$ quasar as would be expected if it were recently formed in a dusty galaxy merger (Sanders et al. 1988, ApJ, 325, 74). er-wave and X-ray emission.

An Expanded Planetarium Outreach Program in Chicago

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S1802.tex 644 34 12 2015 5555514337 5330 % Session 18 -- Astronomers Outside the University
Oral presentation, Monday, 30, 1994, 10:00-11:30

[18.02] An Expanded Planetarium Outreach Program in Chicago

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium)

The Adler Planetarium recently conducted a special outreach program to enrich 5th and 6th grade students before they attended a new sky show titled "African Skies." Nine classrooms in three schools serving an inner city neighborhood were visited each week for three weeks by our team of astronomy educators -- including an experience in the inflatable Starlab planetarium at each school -- and culminating with a visit to the Planetarium by all of the students together. December the object was in the decline phase of a moderate outburst, reaching minimum in early January. In order to get both spectral and polarimetric observations, we used the ISIS double spectropolarimeter, giving us a spectral resolution of 3┼ over the range from 5500-9000┼. This permits both the rapid continuum polarisation variations to be examined from individual exposures (resolution 40 minutes, provided by four individual integrations with

Educational Programs at the Lake Afton Public Observatory

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fferent positions of the calcite retarder) anS1803.tex 644 34 12 4415 5555512606 5334 % Session 18 -- Astronomers Outside the University
Oral presentation, Monday, 30, 1994, 10:00-11:30

[18.03] Educational Programs at the Lake Afton Public Observatory

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.)

The Lake Afton Public Observatory was founded 14 years ago as a joint project of the city, county, local schools, and Wichita State University to provide educational programs for the public and school children. A staff of 4 professional astronomers presents daytime and evening programs at the Observatory and makes presentations in schools to over 20,000 people per year. Programs are scheduled 6 days a week during the academic year and 3 days a week in the summer.

Our public programs deviate significantly from the traditional observatory open house by following a specific theme. Selection and discussion of each object is centered on that theme. For example, a program on The Life Story of a Star would view a diffuse nebula (to discuss star formation), a young star cluster (to discuss one outcome of star formation), a double star (to discuss how the properties of stars are determined), and a planetary nebula (to discuss the death of a star).

To complement the observing experiences of our visitors, we have developed a wide range of interactive exhibits to develop the concepts touched on in the viewing programs. We have also developed exhibit lending kits for extended use in school classrooms, educational games, activity manuals for teachers, and short videos to introduce single concepts in the classroom. In the past year we have begun to offer a series of workshops for in-service teachers to expand their knowledge of astronomy and to provide them with additional resources for teaching astronomy.

This work is supported in part by NSF EPSCoR grant OSR-9255223.

ts of this object (Sillapaa et al 1988, Kidger et al 1992), which has been interpreted as due to a binary black hole (Sillapaa et al 1988). This model predicts an outburst at some

A Satellite Operations Class for Teachers

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me in 1994. If the Winter 1993-94 eruption corresponds to theS1804.tex 644 34 12 4434 5555513314 5333 % Session 18 -- Astronomers Outside the University
Oral presentation, Monday, 30, 1994, 10:00-11:30

[18.04] A Satellite Operations Class for Teachers

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB)

ASTRO 650 is a self-contained teacher training class on the mission operation of a satellite-based astronomy project which has been offered through a collaboration between UCB's Center for Extreme Ultraviolet Astrophysics (CEA) and San Francisco State University's (SFSU) Physics and Education Departments. The class, funded by a NASA Astrophysics AGSE grant, utilizes the Extreme Ultraviolet Explorer (EUVE) NASA satellite mission as a test case for educational outreach. The underlying theme of the class focuses on how scientists carry out research. Emphasis is given to problem-solving techniques with specific examples taken from the pre and postlaunch stages of the EUVE mission. The class, first offered during the Spring semester of 1994, involves weekly two-hour lectures at SFSU and weekly three-hour lab sessions at CEA. The teachers are taught the computer skills and space astrophysics concepts needed to perform hands-on analysis and interpretation of the EUVE satellite data. The last third of the class is dedicated to a final project for groups of the teachers to develop units/activities/materials based on EUVE that they can take back to the classroom. The final projects include implementation and assessment plans. This model treats teachers as professionals, allowing them to collaborate with scientists and to learn about curriculum development---an important aspect of their professional growth. We will give a summary of class content and present a few of the lesson plans developed by the teachers. This work has been supported by NASA contract NAS5-29298. Class support has been provided by a NASA supplemental grant for education. ta will help to elucidate this question, apart from supplying valuable information on the emission processes in active galactic nuclei. References:

Electromagnetic Radiation: A Curriculum Unit for High School Students

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llanpaa A., Haarala S., Valtonen M., Sundelius B., Byrd G.G, 1988, ApJ, 325, S1805.tex 644 34 12 4562 5555513315 5337 % Session 18 -- Astronomers Outside the University
Oral presentation, Monday, 30, 1994, 10:00-11:30

[18.05] Electromagnetic Radiation: A Curriculum Unit for High School Students

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB)

The main goal of the new satellite operations class offered by UC Berkeley in collaboration with San Francisco State University is to provide teachers with detailed information about the goals, phases, and results of NASA's Extreme Ultraviolet Explorer (EUVE) satellite mission. One of the outcomes of this class is to create new lesson plans, curricula for elective courses, and non-traditional teaching techniques and methods, all of which may be incorporated in schools in order to develop students' cognitive interest in science. The information about this unique NASA satellite mission may be presented to high school students in many different ways: class discussions, extra-curricular research assignments, expositions for school museums of science, computer animations, science conferences, educational games, etc. Another approach is to infuse the material related to this project directly into the existing science curricula. The unit ``Electromagnetic Radiation'' presents us with a variety of opportunities to include scientific information related to the EUVE mission in the most natural way. The following issues related to modern astrophysics may be introduced and discussed in this unit: the position that EUV radiation occupies on the electromagnetic spectrum, the sources that emit this type of radiation, the properties and characteristics of this radiation in comparison with other types of electromagnetic waves, and the methods used to detect and analyze EUV and other types of radiation during NASA missions. We will present an overview and a specific detailed example related to this curriculum unit. This work has been supported by NASA contract NAS5-29298. Class support has been provided by a NASA supplemental grant for education. Travel made possible by Research Corporation.

the emission processes in active galactic nuclei. References:

Geminga as Seen by the HST

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llanpaa A., Haarala S., Valtonen M., Sundelius B., Byrd G.G, 1988, ApJ, 325, S1901.tex 644 34 12 3207 5555512444 5331 % Session 19 -- Rossi Prize Lecture
Oral presentation, Monday, 30, 1994, 11:40

[19.01] Geminga as Seen by the HST

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI)

The crucial piece of information still lacking for the understanding of Geminga is the object's distance. Comparing the measured gamma-ray flux with the known neutron star rotational energy loss, one obtains values anywhere between few pc to 300 pc, an upper limit not too far from the one derived from the IS X-ray absorption. \\Exploiting the post-refurbishment capabilities of the HST instruments, we plan to measure (or to put limit on) Geminga's parallactic displacement. This will be done in Cycle 4 with three sets of WFPC2 observations already scheduled near the spring and fall equinoxes, when the expected parallactic displacement is maximum. The program started on March 18, and the results of the first observations will be reported. \\Meanwhile, ground based optical observations, taken fron the New Technology Telescope of the European Southern Observatory, also in 1994, have confirmed the high proper motion of the optical counterpart. natural way. The following issues related to modern astrophysics may be introduced and discussed in this unit: the position that EUV radiation occupies on the electromagnetic spectrum, the sources that emit this type of radiation, the properties and characteristics of this radiation in comparison with other types of

Interpretation of the New X-ray/$\gamma$-ray Pulsars

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ectromagnetic waves, and the methods used to detect andS1902.tex 644 34 12 5171 5555514164 5335 % Session 19 -- Rossi Prize Lecture
Oral presentation, Monday, 30, 1994, 11:40

[19.02] Interpretation of the New X-ray/$\gamma$-ray Pulsars

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.)

The identification of the $\gamma$-ray source Geminga as a rotation-powered pulsar breaths new life into several of the oldest and most difficult problems in high-energy astrophysics. Among these are 1) the interpretation of the unidentified $\gamma$-ray sources in the Galactic plane, 2) the location and physics of $\gamma$-ray emission in rotation-powered pulsars, and 3) the study of magnetized neutron star atmospheres and cooling interiors via their thermal soft X-ray emission. Geminga is the first pulsar which is undetected in the radio. Apart from this unsurprising fact, Geminga is neither unique nor unusual. Rather, it is the prototype of a new class of pulsars whose X-ray and $\gamma$-ray properties are similar, and which have already afforded great progress in understanding the aforementioned issues. The discovery that Geminga and other middle-aged pulsars are capable of channeling a large fraction of their spin-down power into $\gamma$-rays bolsters the hypothesis that most of the unidentified $\gamma$-ray sources in the Galactic plane are pulsars, many of which could be radio-quiet. The high $\gamma$-ray efficiencies of Geminga and PSR 1055--52, together with their large soft X-ray modulation, supports the model in which $\gamma$-rays are generated in the outer magnetosphere of a dipole which is nearly orthogonal to the spin axis. The thermal X-ray emission is of special importance because it is the only source of information about the surface magnetic field geometry. All the soft X-ray pulsars for which high quality data exist have single-peaked profiles, which argues against a simple centered dipole. These same pulsars have an additional, tiny region of hotter thermal emission which can be interpreted as the open field line polar cap which is heated by particles flowing inward from the magnetosphere accelerator. Beyond the simplest blackbody interpretation of these data, magnetic effects on the opacity can modify the emergent spectra, and circumstellar resonant scattering can shape the pulse profiles. Recent observations and theories of these phenomena will be reviewed. 658 is not redder than the average low $z$ quasar as would be expected if it were recently formed in a dusty galaxy merger (Sanders et al. 1988, ApJ, 325, 74). er-wave and X-ray emission.

The Foreground of the Cosmic X-ray Background

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S2001.tex 644 34 12 4637 5555513105 5324 % Session 20 -- Cosmic X-Ray and Microwave Background
Oral presentation, Monday, 30, 1994, 2:00-3:30

[20.01] The Foreground of the Cosmic X-ray Background

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA)

We discuss the local X-ray volume emissivity at hard bands (2 - 10 keV) from the cross-correlation between surface brightness fluctuation of the cosmic X-ray background and nearby galaxies. We have found correlation signals between HEAO 1 A2 surface brightness $I$ and number counts $N$ of IRAS/ESO/UGC galaxies of $W_{xg} \equiv \frac{\langle \delta I \, \delta N \rangle} {\langle I \rangle \langle N \rangle} \sim (3-10) \times 10^{-3}$. We have constructed a detailed model explaining the correlation signal in terms of the local volume emissivity. The correlation is contributed by the Poisson noise process where the correlating sample galaxies themselves emit X-rays. In this case, the correlation between the X-ray luminosity of galaxies and the infrared luminosity (or optical diameter) should be taken into account to evaluate its contribution to $W_{xg}$. Also, for a low spatial resolution experiment such as the HEAO 1 A2, the clusterings of the X-ray sources with the sample galaxies contribute to $W_{xg}$. We present the formulation to take these effects into account for the analysis.

Monte-Carlo simulations have been made to simulate the correlation. These are useful in direct comparison with the observations and estimating the uncertainty due to the finite number of sources contributing to the correlation.

The results are consistent with the models where the 2 - 10 keV volume emissivity is ($\rho_x \sim 4 \times 10^{38} h_{50} erg\,s^{-1} \, Mpc^{-3}$), dominated by the AGN component (with $L_x > 10^{42} h_{50}^{-2} erg\,s^{-1}$ ). This provides a constraint at the present epoch to models of the cosmic X-ray background with evolving populations of sources.

This presentation represents a part of TM's dissertation toward the fulfillment of the PhD requirements of the University of Maryland. \equiv \frac{\langle \delta I \, \delta N \rangle} {\langle I \rangle \langle N \rangle}

UCSB South Pole Degree Scale CMB Anisotropy Program: Status and Results

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im (3S2002.tex 644 34 12 2341 5555512354 5320 % Session 20 -- Cosmic X-Ray and Microwave Background
Oral presentation, Monday, 30, 1994, 2:00-3:30

[20.02] UCSB South Pole Degree Scale CMB Anisotropy Program: Status and Results

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA)

The UC Santa Barbara CMB anisotropy group has made three excursions to the South Pole to obtain data on degree scale anisotropies. The most recent trip occurred from November, 1993 to January, 1994. Data were taken with the UCSB Advanced Cosmic Microwave Explorer (ACME), using two different receivers, operating from 26-36 GHz and from 38- 45 GHz. The receivers incorporate High Electron Mobility Transistor (HEMT) amplifiers operated at liquid Helium temperatures, and acheived noise temperatures of 15 K. Status of the systems and sample data will be presented. laxies themselves emit X-rays. In this case, the correlation between the X-ray luminosity of galaxies and the infrared luminosity (or optical diameter) should be taken into account to evaluate its contribution to $W_{xg}$. Also, for a low spatial resolution

The Spectral Index of Large Scale Anisotropies in the Cosmic Microwave Background Radiation

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periment such as the HEAO 1S2003.tex 644 34 12 2353 5555513033 5317 % Session 20 -- Cosmic X-Ray and Microwave Background
Oral presentation, Monday, 30, 1994, 2:00-3:30

[20.03] The Spectral Index of Large Scale Anisotropies in the Cosmic Microwave Background Radiation

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago)

The large angular scale anisotropy of the cosmic microwave background can often be parameterized by a spectral index, $n$, and a quadrupolar amplitude, $Q$. Applying a new statistical measure to data from the Far Infra-Red Survey (FIRS), we form a contour plot of the likelihood for cosmological models with $-1 < n < 3$ and $0 \le Q \le 50~\mu{\rm K}$. We find that the likelihood is maximum at $(n, Q) = (1.0,19\mu\mbox{K})$. For $n = 1$ the likelihood falls to half its maximum at $Q \approx 14\mu\mbox{K}$ and $25\mu\mbox{K}$ and for $Q = 19\mu$K the likelihood falls to half its maximum at $n \approx 0.5$ and $1.4$.

mselves emit X-rays. In this case, the correlation between the X-ray luminosity of galaxies and the infrared luminosity (or optical diameter) should be taken into account to evaluate its contribution to $W_{xg}$. Also, for a low spatial resolution

The Saskatoon Experiment: A Measurement of the Anisotropy in the Cosmic Microwave Background

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periment such as the HEAO 1S2004.tex 644 34 12 2233 5555513451 5321 % Session 20 -- Cosmic X-Ray and Microwave Background
Oral presentation, Monday, 30, 1994, 2:00-3:30

[20.04] The Saskatoon Experiment: A Measurement of the Anisotropy in the Cosmic Microwave Background

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University)

We present an overview of the instrumentation and scan strategy used to observe the cosmic microwave background radiation from Saskatoon, Saskatchewan. This degree scale anisotropy experiment has maximum sensitivity at a coherence angle, $\theta_c=1.2^\circ$. Multifrequency and polarization coverage from 26 to 46 GHz is obtained with two independent radiometers which are used on an off-axis telescope. A discussion of systematic error discrimination and investigations will be presented. half its maximum at $n \approx 0.5$ and $1.4$. mselves emit X-rays. In this case, the correlation between the X-ray luminosity of galaxies and the infrared luminosity (or optical diameter) should be taken into account to evaluate its contribution to $W_{xg}$. Also, for a low spatial resolution

Results from Saskatoon: A Measurement of the Anisotropy in the Cosmic Microwave Background

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periment such as the HEAO 1S2005.tex 644 34 12 2404 5555513457 5330 % Session 20 -- Cosmic X-Ray and Microwave Background
Oral presentation, Monday, 30, 1994, 2:00-3:30

[20.05] Results from Saskatoon: A Measurement of the Anisotropy in the Cosmic Microwave Background

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University)

We present results from an experiment designed to measure the anisotropy in the cosmic microwave background at degree angular scales. This experiment has now run for two seasons. Data from the first season (SK93) shows fluctuations of amplitude $33_{-9}^{+10} \mu\,$K, at a 1.2\deg~correlation angle, with a spectral index in temperature of $-0.3_{-1.2}^{+0.7}$. Preliminary results from the second season (SK94) with extended frequency coverage will also be presented. These data allow a more precise measurement of the observed anisotropy, and improved limits on the spectral index.

ation from Saskatoon, Saskatchewan. This degree scale anisotropy experiment has maximum sensitivity at a coherence angle, $\theta_c=1.2^\circ$. Multifrequency and polarization coverage from 26 to 46 GHz is obtained with two

AMANDA Results from the 1993-94 South Pole Deployment

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dependent radiometers whicS2006.tex 644 34 12 2571 5555513066 5332 % Session 20 -- Cosmic X-Ray and Microwave Background
Oral presentation, Monday, 30, 1994, 2:00-3:30

[20.06] AMANDA Results from the 1993-94 South Pole Deployment

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden)

The Antarctic Muon and Neutrino Detector Array (AMANDA) collaboration has successfully deployed four strings of optical modules at the south pole. Our preliminary results shows that AMANDA detects muons in coincidence with the South Pole Air Shower Experiment. We will present our measurements of the optical properties of the ice at a depth of 800 -- 1000 meters, the operating characteristics of the four string array, and a review of future plans.

should be taken into account to evaluate its contribution to $W_{xg}$. Also, for a low spatial resolution

{\it Young Scholars Program}: Are we changing any attitudes?

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periment such as the HEAO 1S201.tex 644 34 12 2634 5555513173 5244 % Session 2 -- Education
Display presentation, Monday, 30, 1994, 9:20-6:30

[2.01] {\it Young Scholars Program}: Are we changing any attitudes?

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa)

The Young Scholars Program , at the University of Northern Iowa, is a summer program in which students gain hands-on experience in the physical sciences and mathematics. Within this program, students gain experiences that they do not always have in the regular classroom through student-led discussions, lab investigations, and individual projects. The Young Scholars Program was used to investigate the question of student attitudes towards science and the learning environment. There was no change in attitude of science found. It was found that there are definite differences in attitude of learning environment between the normal classroom and the Young Scholars classroom. The most common attitude statements will be presented and arguments given for the importance of these types of experiences for students. luate its contribution to $W_{xg}$. Also, for a low spatial resolution

Cooperative Learning Strategies for Astronomy Classes

Previous abstract Next abstract

periment such as the HEAO 1S202.tex 644 34 12 1707 5555514271 5245 % Session 2 -- Education
Display presentation, Monday, 30, 1994, 9:20-6:30

[2.02] Cooperative Learning Strategies for Astronomy Classes

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College)

Cooperative learning strategies can be an effective means to teach astronomy. In both community college and large university settings students work in small groups on structured tasks such as laboratory exercises, problem solving, or discussing astromomy topics. In addition to addressing general methods for implementing cooperative learning, potential difficulties will also be discussed. Sample cooperative exercises will be available. o investigate the question of

High-Dispersion CCD Astronomical Spectroscopy in an Undergraduate Lab

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udent attitudes towards sS203.tex 644 34 12 3446 5555513267 5254 % Session 2 -- Education
Display presentation, Monday, 30, 1994, 9:20-6:30

[2.03] High-Dispersion CCD Astronomical Spectroscopy in an Undergraduate Lab

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech)

Experiments in high-dispersion spectroscopy are accessible to undergraduate students in astronomy, provided appropriate instrumentation is available. As part of a project to develop exercises, techniques, and instrumentation for astronomical spectroscopy, we have performed several experiments using a CCD camera as the detector, and with a combination of spectrograph configurations (both commercial and assembled from individual optical/mechanical components) and methods of light insertion (including relay mirrors and optical fibers). We show that the lack of a large telescope and of a commercial long-focal length spectrograph, both of which are expensive, is not an absolute impediment to the performance of these experiments. This work is therefore likely to be of interest to those who have CCD cameras but lack the other two instruments. The equipment also serves well for experiments in spectroscopy of laboratory sources, such as the Zeeman effect in mercury. This work was supported in part by NSF grant DUE-9252109, and in part by The Pew Charitable Trusts through a grant to the New England Consortium for Undergraduate Science Education. roject to develop exercises, techniques, and instrumentation for astronomical spectroscopy, we have performed several experiments using a CCD camera as the detector, and with a combination of spectrograph

The Very Small Array Sky Survey

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nfigurationS204.tex 644 34 12 2254 5555514217 5245 % Session 2 -- Education
Display presentation, Monday, 30, 1994, 9:20-6:30

[2.04] The Very Small Array Sky Survey

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University)

Preliminary results of the Very Small Array Sky Survey (VSASSY) will be presented. Observations are being made with the student built two dish interferometer in the meridian drift scan mode of the 21cm radio sky from $-30\deg$ to $+75\deg$ declination. Position and relative intensity measurements of several calibration sources will be included. This project demonstrates the feasibility of radio astronomy being introduced at an undergraduate level. This is useful to both broaden the perspective of Astronomy students and to introduce them to important data analysis techniques often not covered in the standard curriculum.

t between the normal classroom and the Young Scholars classroom. The most common attitude statements will be presented and arguments given for the importance of these types of experiences for students. luate its contribution to $W_{xg}$. Also, for a low spatial resolution

Radio Observations of Binary Pulsars

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periment such as the HEAO 1S2101.tex 644 34 12 3765 5555512437 5335 % Session 21 -- Pulsars
Oral presentation, Monday, 30, 1994, 2:00-3:30

[21.01] Radio Observations of Binary Pulsars

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University), Zaven Arzoumanian (Princeton U.)

I describe recent timing and polarimetric observations of a number of binary pulsar systems with implications for theories of binary evolution and relativistic gravity.

In the PSR~B1957+20 system, we have detected non-secular orbital period changes similar to those seen in other close binaries but previously unknown in a pulsar system; such orbital variability may imply that the pulsar's low-mass companion is magnetically active or may be the result of a varying mass-loss rate or emission geometry from the companion's surface as it is heated by radiation from the pulsar. In the systems containing PSRs B1802$-$07 and B2303+46, new and refined measurements, respectively, of the rate of periastron advance have yielded within the framework of General Relativity the total mass of each system and constrained the individual masses of their components. High time-resolution polarimetry of PSR B1534+12 has provided the geometry of the pulsar radio beam, constraining the spin-orbital misalignment of the visible neutron star; we also describe a study of pulse shape variability for this pulsar as a means of detecting orbital aberration and relativistic precession of the pulsar spin axis. We have refined the spin, astrometric, and orbital parameters of PSRs B0655+64, B0820+02, and B1820$-$11, and improved the limits on dipolar gravitational radiation, violation of the Strong Equivalence Principle, and time-variability of the universal constant of gravitation $G$ attainable with these timing experiments.

Orbital Period Variability in PSR B1957+20: Evidence for a Tidally Powered Star

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soft X-raS2102.tex 644 34 12 3363 5555513471 5327 % Session 21 -- Pulsars
Oral presentation, Monday, 30, 1994, 2:00-3:30

[21.02] Orbital Period Variability in PSR B1957+20: Evidence for a Tidally Powered Star

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University), Zaven Arzoumanian (Princeton U.), J.H. Applegate (Dept. of Astronomy, Columbia U.), J. Shaham (Dept. of Physics, Columbia U.)

Recent observations indicate that the eclipsing pulsar binary PSR B1957+20 undergoes alternating epochs of orbital period increase and decrease. We apply a model developed to explain orbital period changes of alternating sign in other close binaries to the PSR B1957+20 system and find that it fits the pulsar observations well. The novel feature of the PSR B1957+20 system is that the energy flow in the companion needed to power the orbital period change mechanism can be supplied by tidal dissipation, making the companion the first identified tidally powered star. The flow of energy in the companion drives magnetic activity, which underlies the orbital period variations. The magnetic activity and the wind driven by the pulsar irradiation results in a torque on the spin of the companion which holds the companion out of synchronous rotation, causing tidal dissipation of energy. We propose that the progenitor system had a $\simeq 2$ hr orbital period and a companion mass of $0.1 - 0.2\>M_\odot$, and the system is evolving to longer orbital periods by mass and angular momentum loss on a time scale of $10^8$ years. 1820$-$11, and improved the limits on dipolar gravitational radiation, violation of the Strong Equivalence Principle, and time-variability of the universal constant of gravitation $G$ attainable with these timing experiments.

Multifrequency Radio Properties of the Crab Pulsar

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soft X-raS2103.tex 644 34 12 3455 5555513271 5330 % Session 21 -- Pulsars
Oral presentation, Monday, 30, 1994, 2:00-3:30

[21.03] Multifrequency Radio Properties of the Crab Pulsar

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University), Zaven Arzoumanian (Princeton U.), J.H. Applegate (Dept. of Astronomy, Columbia U.), J. Shaham (Dept. of Physics, Columbia U.), D. A. Moffett, T. H. Hankins (NMIMT)

We report phased array VLA and Arecibo observations of the Crab pulsar at multiple frequencies and high time resolution. Average profiles were recorded at 0.33, 1.4, 4.8, and 8.4 GHz, as well as high time resolution data from the ``giant'' pulses. Coherent dedispersion of the giant pulse data reveals significant intensity structure on a 30 -- 50 ns time scale.

Some giant pulses rise very fast, then decay exponentially. Exponential time constants and autocorrelation widths of these pulses have been computed for each of the observed frequencies. At low frequencies, the pulses exhibit known interstellar scattering pulse broadening. But at high frequencies, the pulse shapes suggest another form of scattering is occurring, perhaps associated with the nebula or the magnetosphere of the pulsar itself.

The morphology of the average profiles also changes with frequency. At low frequency, 0.33 GHz, a known steep-spectrum precursor of the main pulse exists which does not appear at 1.4 GHz. At 4.8 and 8.4 GHz, two more components appear after the interpulse. The separation between the main and interpulse decreases above 1.4 GHz. In addition, the relative amplitudes of the main and interpulse change with frequency, implying either an effect of the emission geometry or a difference in spectral index.

l radiation, violation of the Strong Equivalence Principle, and time-variability of the universal constant of gravitation $G$ attainable with these timing experiments.

Optical Observations of PSR1509-58

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soft X-raS2104.tex 644 34 12 3207 5555512514 5323 % Session 21 -- Pulsars
Oral presentation, Monday, 30, 1994, 2:00-3:30

[21.04] Optical Observations of PSR1509-58

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University), Zaven Arzoumanian (Princeton U.), J.H. Applegate (Dept. of Astronomy, Columbia U.), J. Shaham (Dept. of Physics, Columbia U.), D. A. Moffett, T. H. Hankins (NMIMT), Patrizia A. Caraveo (IFC CNR, Milano), Giovanni F. Bignami (IFCC NR, Milano), Sandro Mereghetti (IFC CNR, Milano), Roberto Mignani (Universita di Milano), Christian Gouiffes (SAP, DAPNIA,Saclay)

PSR 1509-58 (P=150 msec) is unique in many respects: it is the pulsar with the highest period derivative, hence probably the one with the highest B known so far (about $10 ^{13} G$). This, in spite of its relatively long period, makes itthe second youngest pulsar after the Crab nebula. \\A possible optical counterpart has been discovered by Caraveo, Mereghetti and Bignami (Ap.J. Lett in press) using the New Technology Telescope of the EuropeanSouthern Observatory in June 93. It is an object of 22nd mag in V, which is seento coincide precisely (better than 0.5 arcsec) with the sub-arcsec radio position of the pulsar. \\More data on the optical counterpart of PSR1509-58 will be collected at the beginning of May using the 3.6 m telescope of the European Southern Observatory.Aim of the observing run is to perform fast photometry of the proposed optical counterpart in order to say a definite word on the pulsar's identification. the main and interpulse change with frequency, implying either an effect of the emission geometry or a difference in spectral index. l radiation, violation of the Strong Equivalence Principle, and time-variability of the universal constant of gravitation $G$ attainable with these timing experiments.

UV-Optical Observations of PSR0656+14 with post-COSTAR HST

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soft X-raS2105.tex 644 34 12 3333 5555512775 5335 % Session 21 -- Pulsars
Oral presentation, Monday, 30, 1994, 2:00-3:30

[21.05] UV-Optical Observations of PSR0656+14 with post-COSTAR HST

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University), Zaven Arzoumanian (Princeton U.), J.H. Applegate (Dept. of Astronomy, Columbia U.), J. Shaham (Dept. of Physics, Columbia U.), D. A. Moffett, T. H. Hankins (NMIMT), Patrizia A. Caraveo (IFC CNR, Milano), Giovanni F. Bignami (IFCC NR, Milano), Sandro Mereghetti (IFC CNR, Milano), Roberto Mignani (Universita di Milano), Christian Gouiffes (SAP, DAPNIA,Saclay), France A. Cordova (NASA HQ), Guy S. Stringfellow, and George G. Pavlov (Penn State Univ)

Pulsars emit radiation in many wavebands, including the optical, UV, and X-ray domains. This radiation can arise from both thermal and nonthermal processes, and the relative strengths of their respective contributions depends upon the physical properties of the neutron star magnetosphere and surface atmosphere; e.g., age, magnetic field strength, composition, and (uncertain) interior physics. Soft X-ray detections of a number of pulsars yield temperatures of the order $10^5 - 10^6 $K, indicating that pulsars should be UV bright irrespective of the origin of the radiation. We presently have an HST program using the FOC/f96 to detect several pulsars at UV and optical wavelengths. The first pulsar, PSR0656+14, was observed in mid-Feb 1994 and the results will be reported. This is a relatively young pulsar ($\sim 10^5$ yrs) with properties rather similar to Geminga (P=0.385 s, $B \sim 5\times 10^{12} G$) and has an accurate radio position. The soft X-ray spectrum is thermal-like. The HST/FOC observations have sufficient spatial resolution to preclude source-confusion and background contamination, enabling definitive identification and analysis to be performed. sion geometry or a difference in spectral index. l radiation, violation of the Strong Equivalence Principle, and time-variability of the universal constant of gravitation $G$ attainable with these timing experiments.

Nearly-Aligned Rotator Model of Gamma Ray Pulsars

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soft X-raS2106.tex 644 34 12 5122 5555513130 5316 % Session 21 -- Pulsars
Oral presentation, Monday, 30, 1994, 2:00-3:30

[21.06] Nearly-Aligned Rotator Model of Gamma Ray Pulsars

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University), Zaven Arzoumanian (Princeton U.), J.H. Applegate (Dept. of Astronomy, Columbia U.), J. Shaham (Dept. of Physics, Columbia U.), D. A. Moffett, T. H. Hankins (NMIMT), Patrizia A. Caraveo (IFC CNR, Milano), Giovanni F. Bignami (IFCC NR, Milano), Sandro Mereghetti (IFC CNR, Milano), Roberto Mignani (Universita di Milano), Christian Gouiffes (SAP, DAPNIA,Saclay), France A. Cordova (NASA HQ), Guy S. Stringfellow, and George G. Pavlov (Penn State Univ), J.K. Daugherty (UNCA), A.K. Harding (NASA/GSFC)

We have derived new pulse profiles and energy spectra for gamma ray pulsars, using a polar cap (PC) cascade model in which the inclination $\alpha$ of the magnetic axis is comparable to the cap half-angle $\theta_{pc}$. The model assumes acceleration of electrons above the pulsar surface to energies $\sim10$ TeV. The electrons emit curvature radiation (CR) which is converted by the pulsar B-field to photon-pair cascades in the deep magnetosphere. Since CR-induced PC cascades produce hollow-cone emission regardless of the primary electron beam geometry, observers whose viewing angles $\zeta$ intersect the rim of a single PC see double pulses, which for $\alpha \sim \theta_{pc}$ may vary from 0 to $\sim 180$ degrees. We have examined the $(\alpha,\zeta,\theta_{pc})$ parameter space which can produce doubly peaked model profiles consistent with those observed from the Crab, Vela, and Geminga. We have also considered the effect of the primary beam geometry on peak duty cycles. Our best fits are obtained from models in which acceleration occurs only around the PC rim. The model profiles also show emission between the peaks, corresponding to the phase interval for which the observer viewpoint is outside the PC rim, which may account for the interpulse emission in Vela and Geminga. The same model parameters have produced phase-resolved spectra which are generally consistent with observations, especially for Vela. Our model also allows the possibility of two closely separated peaks, as well as a single broad peak (seen by observers whose viewpoints do not penetrate the PC rim). Since the model beaming factors and detection probabilities are sensitive to PC size, we have considered the dependence of cascade properties on $\theta_{pc}$. One major effect is that the B-field curvature increases with $\theta_{pc}$, leading to enhanced CR and hence more extensive cascades. The high-energy spectral cutoffs are also lowered by more efficient pair conversion. For these enlarged-PC models, our best spectral fits require either a reduced B-field or an extended acceleration zone above the NS surface. iewed. 658 is not redder than the average low $z$ quasar as would be expected if it were recently formed in a dusty galaxy merger (Sanders et al. 1988, ApJ, 325, 74). er-wave and X-ray emission.

Modelling `Warped' Galaxies without Warps

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S2201.tex 644 34 12 4054 5555512471 5324 % Session 22 -- Galaxy Structure and Kinematics
Oral presentation, Monday, 30, 1994, 2:00-3:30

[22.01] Modelling `Warped' Galaxies without Warps

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University), Zaven Arzoumanian (Princeton U.), J.H. Applegate (Dept. of Astronomy, Columbia U.), J. Shaham (Dept. of Physics, Columbia U.), D. A. Moffett, T. H. Hankins (NMIMT), Patrizia A. Caraveo (IFC CNR, Milano), Giovanni F. Bignami (IFCC NR, Milano), Sandro Mereghetti (IFC CNR, Milano), Roberto Mignani (Universita di Milano), Christian Gouiffes (SAP, DAPNIA,Saclay), France A. Cordova (NASA HQ), Guy S. Stringfellow, and George G. Pavlov (Penn State Univ), J.K. Daugherty (UNCA), A.K. Harding (NASA/GSFC), G. R. Roelofs (University of Chicago)

Velocity maps of disk galaxies never look like purely planar, circular flows; other velocity components are invariably present and add asymmetries to the flow maps. The traditional interpretation of a large class of these distortions has been in terms of warped disks, and there is good motivation for this: many edge-on galaxies {\sl are} visibly warped, either in the optical or, especially, in radio observations of neutral hydrogen. In many more galaxies, however, the presumed warp is seen only in velocity maps. Recent numerical experiments by R.~H.~Miller and B.~F.~Smith have found that galaxies can oscillate in radial normal modes with relatively large amplitude (10--20 km/s for a Milky-Way-sized galaxy), and it has long been known that such radial motions produce velocity signatures similar to those in warped disks. Given this, it is reasonable to investigate the extent to which kinematic observations of disk galaxies can be interpreted in terms of planar disks with a radial flow component, rather than warped disks with purely circular flows. We have done this for several galaxies and find that in at least some cases the radial-flow models fit the observations as well as or better than the tilted-rings models do. This implies more generally that, while warps may still be necessary to explain observed kinematic features in many galaxies, less extreme warps (in combination with radial motions) may now suffice. That in turn eases the burden on models attempting to explain the longevity of warps. ce the model beaming factors and detection probabilities are sensitive to PC size, we have considered the dependence of cascade properties on $\theta_{pc}$. One major effect is that the B-field curvature increases with $\theta_{pc}$, leading to enhanced CR and hence more extensive cascades. The high-energy spectral cutoffs are also lowered by more efficient pair conversion. For these enlarged-PC models,

Hydrostatic torii and ring galaxies

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r best spectral fits require either a reduced B-field or anS2202.tex 644 34 12 1361 5555513631 5322 % Session 22 -- Galaxy Structure and Kinematics
Oral presentation, Monday, 30, 1994, 2:00-3:30

[22.02] Hydrostatic torii and ring galaxies

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University), Zaven Arzoumanian (Princeton U.), J.H. Applegate (Dept. of Astronomy, Columbia U.), J. Shaham (Dept. of Physics, Columbia U.), D. A. Moffett, T. H. Hankins (NMIMT), Patrizia A. Caraveo (IFC CNR, Milano), Giovanni F. Bignami (IFCC NR, Milano), Sandro Mereghetti (IFC CNR, Milano), Roberto Mignani (Universita di Milano), Christian Gouiffes (SAP, DAPNIA,Saclay), France A. Cordova (NASA HQ), Guy S. Stringfellow, and George G. Pavlov (Penn State Univ), J.K. Daugherty (UNCA), A.K. Harding (NASA/GSFC), G. R. Roelofs (University of Chicago), W. Klu\'zniak (U. of Wisconsin)

A mass of gas of constant specific angular momentum, which is in hydrostatic equilibrium in an attractive external gravitational potential, assumes the form of a torus reminiscent of structures observed in ring galaxies. distortions has been in terms of warped disks, and there is good motivation for this: many edge-on galaxies {\sl are} visibly warped, either in the optical or, especially, in radio observations of neutral hydrogen. In many more galaxies, however,

On the Intrinsic Shapes of Elliptical Galaxies

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e presumed warp is S2203.tex 644 34 12 2512 5555514254 5324 % Session 22 -- Galaxy Structure and Kinematics
Oral presentation, Monday, 30, 1994, 2:00-3:30

[22.03] On the Intrinsic Shapes of Elliptical Galaxies

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University), Zaven Arzoumanian (Princeton U.), J.H. Applegate (Dept. of Astronomy, Columbia U.), J. Shaham (Dept. of Physics, Columbia U.), D. A. Moffett, T. H. Hankins (NMIMT), Patrizia A. Caraveo (IFC CNR, Milano), Giovanni F. Bignami (IFCC NR, Milano), Sandro Mereghetti (IFC CNR, Milano), Roberto Mignani (Universita di Milano), Christian Gouiffes (SAP, DAPNIA,Saclay), France A. Cordova (NASA HQ), Guy S. Stringfellow, and George G. Pavlov (Penn State Univ), J.K. Daugherty (UNCA), A.K. Harding (NASA/GSFC), G. R. Roelofs (University of Chicago), W. Klu\'zniak (U. of Wisconsin), B. Tremblay \& D. Merritt (Rutgers University)

We examine the distribution of elliptical galaxy intrinsic axis ratios, using the Ryden-Djorgovski sample of apparent axis ratios for 171 galaxies. Unlike previous studies, our technique is fully nonparametric, and places no a priori restrictions on the form of the ellipticity distribution. We find that the frequency function of intrinsic shapes implied by either the oblate or prolate hypotheses is negative at intrinsic axis ratios close to spherical. In other words, we can rule out the hypothesis of axisymmetry for this sample of galaxies. Allowing the intrinsic shapes to be triaxial yields a fully non-negative frequency function. We conclude that a strong case for triaxiality can be made purely on the basis of the distribution of apparent shapes.

rped disks. Given this, it is reasonable to investigate the extent to which kinematic observations of disk galaxies can be interpreted

Planetary Camera Imaging of the Nucleus of M51

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terms of planar disks with a radial flow coS2204.tex 644 34 12 3404 5555512710 5321 % Session 22 -- Galaxy Structure and Kinematics
Oral presentation, Monday, 30, 1994, 2:00-3:30

[22.04] Planetary Camera Imaging of the Nucleus of M51

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University), Zaven Arzoumanian (Princeton U.), J.H. Applegate (Dept. of Astronomy, Columbia U.), J. Shaham (Dept. of Physics, Columbia U.), D. A. Moffett, T. H. Hankins (NMIMT), Patrizia A. Caraveo (IFC CNR, Milano), Giovanni F. Bignami (IFCC NR, Milano), Sandro Mereghetti (IFC CNR, Milano), Roberto Mignani (Universita di Milano), Christian Gouiffes (SAP, DAPNIA,Saclay), France A. Cordova (NASA HQ), Guy S. Stringfellow, and George G. Pavlov (Penn State Univ), J.K. Daugherty (UNCA), A.K. Harding (NASA/GSFC), G. R. Roelofs (University of Chicago), W. Klu\'zniak (U. of Wisconsin), B. Tremblay \& D. Merritt (Rutgers University), Carl J. Grillmair, S.M. Faber (Lick Observatory), J. Jeff Hester, Paul A. Scowen (Arizona State University), Tod R. Lauer (NOAO), and the Members of the Wide Field/Planetary Camera Investigation Definition Team

We present high-resolution, broad- and narrow-band images of the central region of M51 taken with the Planetary Camera of the {\it Hubble Space Telescope}. The $V$-band images show radial dust lanes, roughly aligned with the major axis of the bar, presumably transporting gas to the AGN in the nucleus. The dust lane obscuring the nucleus of the galaxy is more complex than has been previouly reported, being both off-center and having curved appendages extending in different directions. H$\alpha$/[NII] images show several discrete blobs of ionized gas strung along arcs extending both northwards and southwards from the nucleus, describing a leading ``S''-configuration. The forbidden-line images of the extra-nuclear cloud are consistent with a picture in which a very narrow nuclear jet strikes and splatters off of the boundary of a relatively dense cloud of gas in the disk of the galaxy. We briefly discuss the degree to which the jet appears to influence the structure of the interstellar medium surrounding the nucleus.

rally that, while warps may still be necessary to explain observed kinematic features in many galaxies, less extreme warps (in combination with radial motions) may now suffice. That in turn eases the burden on models attempting to explain the

WFPC-2 CMDs of Cepheid Calibration Fields in M33 and M31

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ngevitS2205.tex 644 34 12 2311 5555513144 5320 % Session 22 -- Galaxy Structure and Kinematics
Oral presentation, Monday, 30, 1994, 2:00-3:30

[22.05] WFPC-2 CMDs of Cepheid Calibration Fields in M33 and M31

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University), Zaven Arzoumanian (Princeton U.), J.H. Applegate (Dept. of Astronomy, Columbia U.), J. Shaham (Dept. of Physics, Columbia U.), D. A. Moffett, T. H. Hankins (NMIMT), Patrizia A. Caraveo (IFC CNR, Milano), Giovanni F. Bignami (IFCC NR, Milano), Sandro Mereghetti (IFC CNR, Milano), Roberto Mignani (Universita di Milano), Christian Gouiffes (SAP, DAPNIA,Saclay), France A. Cordova (NASA HQ), Guy S. Stringfellow, and George G. Pavlov (Penn State Univ), J.K. Daugherty (UNCA), A.K. Harding (NASA/GSFC), G. R. Roelofs (University of Chicago), W. Klu\'zniak (U. of Wisconsin), B. Tremblay \& D. Merritt (Rutgers University), Carl J. Grillmair, S.M. Faber (Lick Observatory), J. Jeff Hester, Paul A. Scowen (Arizona State University), Tod R. Lauer (NOAO), and the Members of the Wide Field/Planetary Camera Investigation Definition Team, W.L. Freedman (OCIW), in collaboration with members of the HST Key Project on the Extragalactic Distance Scale, and with members of the WFPC-2 IDT

New WFPC-2 data for M31 and M33 have been obtained as part of the {\it Hubble Space Telescope} Key Project on the Extragalactic Distance Scale. We present deep I-(V-I) color-magnitude diagrams and luminosity functions of a field in the inner region of M33 and a field in Baade's Field IV in M31. In the case of M33, these frames provide both a photometric tie-in to ground-based observations and provide an assessment of the amount of crowding in the vicinity of the Cepheids.

pha$/[NII] images show several discrete blobs of ionized gas strung along arcs extending both northwards and southwards from the nucleus, describing a leading ``S''-configuration. The forbidden-line images of the extra-nuclear cloud are consistent with a picture in which a very narrow nuclear jet

Color-Magnitude Diagrams of the Brightest Stars in the Virgo Galaxy M100: Early Release Observations from HST

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rikes and S2206.tex 644 34 12 3332 5555513142 5323 % Session 22 -- Galaxy Structure and Kinematics
Oral presentation, Monday, 30, 1994, 2:00-3:30

[22.06] Color-Magnitude Diagrams of the Brightest Stars in the Virgo Galaxy M100: Early Release Observations from HST

P.S. Coppi (University of Chicago), F.A. Aharonian, H. V\"olk (Max-Planck-Institut f\"ur Kernphysik), M. Sommer (MPE), K. Hurley, P. Li (UC Berkeley SSL), C. Kouveliotou, G.J. Fishman (MSFC), M. Boer, M. Niel (CESR), J. Laros (U. Arizona), T. Cline (NASA/GSFC), S.Sampson, A.Borione, C.E.Covault, J.W.Cronin, B.E.Fick, L.F.Fortson, K.G.Gibbs,B.J.Newport, T.A.McKay, R.A.Ong, L.J Rosenberg (EFI,U of Chicago), M.Catanese, K.D.Green, A.Kennedy, J.Matthews, D.Nitz, D.Sinclair, J.C. van der Velde (U of Michigan), D.B.Kieda (U of Utah), V. C. Vo (Mankato State U.), J. Hakkila (Mankato State U.), L. M. Pearson (Mankato State U.), C. A. Meegan (NASA/MSFC), D. H. Hartmann (Clemson U.), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), (), B. A. Thompson (Mankato State U.), J. Hakkila (Mankato State U.), V. C. Vo (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), Alar Toomre (MIT), H. D. Aller, P. A. Hughes, M. F. Aller (U. Michigan), C.-Y.Hwang, S.Bowyer (UCB Astron/CEA), S.Kahn (UCB Phys \& Astron), A.Konigl (U Chicago Astron), Paolo Marziani, Jack W. Sulentic, William C. Keel (U. Alabama), Toma\v{z} Zwitter (U. Ljubljana/U. Padova), Massimo Calvani (Padova Obs.), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. Sault (ATNF ), S. M. Simkin (Mich State), E. M. Sadler (Sydney U), R. M. Wagner, H. D. Aller, P. A. Hughes (U. Michigan), J.Glenn, G.D.Schmidt (U.Ariz.), C.B.Foltz (MMTO), F.W. Hamann, T.A. Barlow, E.A. Beaver, E.M. Burbidge, R.D. Cohen, V.T. Junkkarinen and R.W. Lyons (UCSD), A. Siemiginowska, O. Kuhn, F. Fiore, M. Elvis, J. McDowell, B. Wilkes and S. Mathur (SAO), T. Aldcroft (SAO), J. Bechtold (U. Arizona/Steward), M. Elvis (SAO), B.J.Wills (Univ.TX Austin), J.A.Baldwin (CTIO), M.S.Brotherton (Univ.TX Austin), H.Netzer (Tel Aviv Univ.), G.J.Ferland (Univ.KY Lexington), D.Wills (Univ.TX Austin), I.W.A.Browne (Jodrell Bank, Univ. Manchester), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), R.F.Carswell (IOA, Cambridge, U.K.), M.Han (Univ.Wisconsin, Madison), L.K.Herold (MIT and DTM/CIW), B.F.Burke, S.R.Conner, E.J.Gaidos (MIT), T. Kundi\'c (Princeton University Observatory), J.A.Zweerink, A.Kerrick, P.Kwok, R.C.Lamb, D.A.Lewis, G.Mohanty (ISU), J.Buckley, M.Chantell, V.Connaughton, A.C.Rovero, T.C.Weekes (CfA), D.J.Fegan, S.Fennell, J.Quinn (UC Dublin), A.M.Hillas, J.Rose, M.West (U Leeds), M.F.Cawley (St. Patrick's C), C.W.Akerlof, D.Meyer, M.Schubnell (U Mich), J.A.Gaidos, G.Sembroski, J.Wilson (Purdue U), K. D. Gordon \& A. N. Witt (U. of Toledo), C. Blaha, K. Johnson, T. Wyder (Carleton College), A.M.~Watson, T.M.~Tripp, and J.S.~Gallagher (University of Wisconsin -- Madison), C.Winrich, P.N.Appleton (Iowa State University), G.Fabbiano (CfA), F.D.Ghigo (NRAO), P.N.Appleton (Iowa State U.), V. Charmandaris, P. N. Appleton (ISU), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), A.M.N. Ferguson (Johns Hopkins University), R.F.G. Wyse (Johns Hopkins University), J.S. Gallagher (University of Wisconsin--Madison), D.A. Hunter (Lowell Observatory), T.E. Pickering, C.D. Impey (University of Arizona), J. van Gorkom (Columbia University), G.D. Bothun (University of Oregon), R. E. Griffiths, K. U. Ratnatunga, S. Casertano, M. Im, E. W. Wyckoff (Johns Hopkins University), R. A. Windhorst, P. Schmidtke, S. Pascarelle, S. Mutz (Arizona State University), R. S. Ellis, G. Gilmore, K. Glazebrook, R. A. W. Elson (IoA, Cambridge), R. F. Green, V. Sarajedini (NOAO), J. P. Huchra (CfA), G. D. Illingworth, D. C. Koo, A. C. Phillips, D. A. Forbes, M. A. Bershady (Lick Observatory), J. A. Tyson, P. McIlroy (AT\&T Bell Labs), P. Guhathakurta (STScI), Guy S. Miller (Northwestern University), Myeong-Gu Park (Kyungpook National University), D. Kita (U. of Wisconsin--Madison), W. Klu\'zniak (U. of Wisconsin,Copernicus Astronomical Center), M. Coleman Miller (University of Chicago), Frederick K. Lamb (University of Illinois at Urbana-Champaign), T.J.B.Collins, H.M.Van Horn (Univ. of Rochester), U.Lee (Ecole Normal Superiure de Lyon), R.Epstein (Los Alamos Natl. Lab), Dinshaw Balsara (National Center for Supercomputing Applications, Univ. of Illinois), Michael L. Norman, Dinshaw Balsara and Chris O'Dea ( National Center for Supercomputing Applications, Univ. of Illinois), Chris O'Dea, Dinshaw Balsara and Mario Livio ( Space Telescope Science Inst. and NCSA), Chris O'Dea, Dinshaw Balsara and Mario Livio, G. A. Kriss (JHU), G. Lee, A.F. Davidsen, G.A. Kriss, W. Zheng, J.W. Kruk, and C.W. Bowers (Johns Hopkins University), Lev Titarchuk \& Xin-Min Hua (NASA/GSFC USA; ISTS, CANADA) (NASA/GSFC USA; ISTS, CANADA), C.A.Wingate, N.M.Hoffman, R.F.Stellingwerf (LANL), R.F.Stellingwerf, N.M.Hoffman, C.A.Wingate (LANL), J.C. Brandt (LASP/U. Colorado), F.M. Caputo (LASP/U. Colorado), J.T. Hoeksema (Stanford U.), M.B. Niedner, Jr. (NASA/Goddard), Y. Yi (LASP/U. Colorado), J.G. Hills, M.P. Goda (LANL), D.M. Kary (UCSB), J.J. Lissauer (SUNYSB), K. Hurley (UC Berkeley SSL), M. Boer, M. Niel (CESR), C. Kouveliotou, C. Meegan, G.J. Fishman (MSFC), B.L. Dingus, P.Sreekumar (USRA/GSFC), D.L. Bertsch, C.E. Fichtel, R.C. Hartman, S.D. Hunter, D.J. Thompson (NASA/GSFC), G. Kanbach, H.A. Mayer-Hasselwander, C. von Montigny, M. Sommer (MPI), Y.C. Lin, P.L. Nolan, P.F. Michelson (Stanford), D.A. Kniffen (Hampden-Sydney), J.R. Mattox (CSC/GSFC), E.J. Schneid (Grumman), J.M. Ryan, A. Connors, R.M. Kippen (UNH), V. Sch\"onfelder (MPE), W. Hermsen (SRON-Leiden), L. Hanlon, K. O'Flaherty (ESTEC), K. Hurley (UCB), B. McNamara, T. Harrison (NMSU), H. Pederson (Copenhagen U.), J. M. Horack (NASA/MSFC), and A. G. Emslie (UAH), David M. Caditz (Montana State University), J. Hakkila (Mankato State U.), C. A. Meegan (NASA/MSFC), J. M. Horack (NASA/MSFC), G. J. Fishman (NASA/MSFC), G. N. Pendleton (UAH), R. B. Wilson (NASA/MSFC), M. N. Brock (NASA/MSFC), W. S. Paciesas (UAH), M. S. Briggs (UAH), D. P. Whitmire, P. G. Whitman, J. J. Matese (Southwestern Univ.), A. G. Emslie (UAH), and J. M. Horack (NASA/MSFC), A. G. Emslie, W.H.Lahaise, S.P.Bhavsar (U.Kentucky), G.J. Stacey, G.E. Gull, T.L. Hayward, H. Latvakoski, and L. Peng (Dept. of Astronomy, Cornell University), R.L.Akeson, J.E.Carlstrom, J.A.Philliips, D.P.Woody (Caltech), J. Zmuidzinas, G. Blake, J. Carlstrom, J. Keene, D. Miller, G. Ugras (Caltech), S. D. Doty, C. M. Leung (Rensselaer), D. C. Lis (Caltech), Karl R. Stapelfeldt (JPL), C. J. Burrows (STSci), J. Krist (STSci), J. Trauger (JPL), G. Ballester (Michigan), S. Casertano (Johns Hopkins), J. Clarke (Michigan), D. Crisp (JPL), J. Gallagher (Wisconsin), R. Griffiths (Johns Hopkins), J. Hester (Arizona State), J. Hoessel (Wisconsin), J. Holtzman (Lowell), J. Mould (Mt. Stromlo), P. Scowen (Arizona State) (A. Watson) (Wisconsin), J. Westphal (Caltech), D.K. Lynch, R.W. Russell, J.A. Hackwell (The Aerospace Corporation), S. Fajardo-Acosta (SUNY), R. Knacke (Penn State Erie), M. Hanner (JPL), C. Telesco (NASA MSFC), T. M. Herbst (MPIA Heidelberg), C. D. Koresko (Univ. Texas, Austin), Ch. Leinert (MPIA Heidelberg), R.E.Stencel (University of Denver), D.E.Backman (Franklin\&Marshall College), Steven D. Bloom (Boston U. and Technion), M.J. Ledlow (UNM/NRAO/NMSU), K. C. Chambers (IfA) (IfA), O. Kuhn (Harvard University), M. Elvis (SAO), J. Bechtold, M. Rieke, R. Cutri (Steward Obsevatory), B. Wilkes (SAO), Mark R. Kidger, Jose A. de Diego, Jose N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), S. Mathur, B. Wilkes, M. Elvis and F. Fiore (SAO), JosÚ A. de Diego, JosÚ N. Gonzalez-Perez (Instituto de Astrofisica de Canarias), Phil Charles (Department of Astronomy, Oxford University), Mark Kidger (Instituto de Astrofisica de Canarias), Eric D. Carlson (The Adler Planetarium), D. R. Alexander (Wichita St. Univ. \& Lake Afton Public Obs.), G. R. Novacek (Lake Afton Public Obs.), I.Hawkins (CEA/UCB), S.Lea (SFSU), R.Battle (UCB Grad. Ed./CEA), J.Moriarta (UCB/CEA), R.F.Malina (CEA/UCB), N.Levandovsky (Galileo HS/CEA), I.Hawkins, R.F.Malina (CEA/UCB), Giovanni F. Bignami (IFC-CNR,Milano), Patrizia A. Caraveo (IFC-CNR,Milano), Sandro Mereghetti (IFC-CNR,Milano), Roberto Mignani (Universita' di Milano), Laurence Taff (STScI), J.P. Halpern (Columbia U.), T. Miyaji (NASA/GSFC,U. Maryland), E. Boldt, K. Jahoda (NASA/GSFC), O. Lahav (IoA), J.Gundersen, T.Gaier, T.Koch, M.Lim, P.Lubin, P.Meinhold, J.Staren, A.Wuensche (UCSB and CfPA), K.Ganga, L.Page (Princeton), E.Cheng (NASA/GSFC), S.Meyer (Chicago), E.J. Wollack, N.C. Jarosik, C.B. Netterfield, L.A. Page, D. Wilkinson (Princeton University), C.B. Netterfield, N.C. Jarosik, L.A. Page, D. Wilkinson, E.J. Wollack (Princeton University), P.Mock, S.Barwick, R.Porrata, E.Schneider, G.Yodh (University of California, Irvine), A.Goobar, D.Lowder, T.Miller, P.B.Price, A.Richards (University of California, Berkeley), A.Coulthard, K.Engel, L.Gray, F.Halzen, J.Jacobsen, V.Kandhadai, I.Liubarsky, R.Morse, S.Tilav (University of Wisconsin, Madison), A.Bouchta, B.Erlandsson, P.O.Hulth, W.Sun, C.Wlack (Stockholm University, Sweden), S.Carius, L.Hallgren (University of Uppsala, Sweden), D. Hinz Tibben (Univ. of N. Iowa), M. Hollabaugh (Normandale Community College), S.J.Ratcliff, A.A.Ambuske (Middlebury Coll.), S. Kono (Bowdoin Coll.), R. Lu (Caltech), M. Roberts, N. Owen, G. Spear, L. Cominsky (Sonoma State University), Zaven Arzoumanian (Princeton U.), J.H. Applegate (Dept. of Astronomy, Columbia U.), J. Shaham (Dept. of Physics, Columbia U.), D. A. Moffett, T. H. Hankins (NMIMT), Patrizia A. Caraveo (IFC CNR, Milano), Giovanni F. Bignami (IFCC NR, Milano), Sandro Mereghetti (IFC CNR, Milano), Roberto Mignani (Universita di Milano), Christian Gouiffes (SAP, DAPNIA,Saclay), France A. Cordova (NASA HQ), Guy S. Stringfellow, and George G. Pavlov (Penn State Univ), J.K. Daugherty (UNCA), A.K. Harding (NASA/GSFC), G. R. Roelofs (University of Chicago), W. Klu\'zniak (U. of Wisconsin), B. Tremblay \& D. Merritt (Rutgers University), Carl J. Grillmair, S.M. Faber (Lick Observatory), J. Jeff Hester, Paul A. Scowen (Arizona State University), Tod R. Lauer (NOAO), and the Members of the Wide Field/Planetary Camera Investigation Definition Team, W.L. Freedman (OCIW), in collaboration with members of the HST Key Project on the Extragalactic Distance Scale, and with members of the WFPC-2 IDT, B.F.Madore (CIT/JPL/NED), in collaboration with members of the HST Key Project on the Extragalactic Distance Scale, and with members of the WFPC-2 IDT

We present color-magnitude diagrams reaching five magnitudes down into the luminosity function for $\sim$ 10,000 of the brightest stars in the Virgo galaxy M100. These data were derived from BVR WFPC-2 images obtained as part of the Early Release Observations made by the Hubble Space Telescope shortly after the repair mission in Dec. 1993. The V luminosity function for the blue plume is found to have a slope of 0.67 consistent with Local Group studies. Many of the very brightest objects (first appearing at V = 20.5 mag) are clearly identified as complex multiple systems, association cores, and/or young clusters mostly residing in and along the high-density spiral arms. Cepheid candidates have been identified based on their apparent magnitude and color. Deeper VI exposures of less crowded adjacent fields in M100, taken as part of the HST Key Project on the Extragalactic Distance Scale, will also be presented and discussed.