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
- 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
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.