AAS Meeting #193 - Austin, Texas, January 1999
Session 107. (Quasars and Blazars-) High Luminosity AGN and their Environments
Display, Saturday, January 9, 1999, 9:20am-4:00pm, Exhibit Hall 1

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[107.06] The ISO/NASA AGN Key Project with ISO to Study the Far-IR to X-Ray Spectral Energy Distributions of Quasars: The Infrared Data

E. J. Hooper, B. J. Wilkes (SAO), K. McLeod (Wellesley), M. Elvis (SAO), C. D. Impey (Arizona), C. Lonsdale (IPAC), M. A. Malkan (UCLA), J. McDowell (SAO)

A substantial fraction of the bolometric luminosity of many quasars is emitted in the infrared (Elvis et al.~1994, ApJS, 95, 1). Observations with ISO are expanding the range of quasars which have mid and far infrared data. ISO's advantages over IRAS include better spatial resolution, more bandpasses, and pointed observations which provide deeper flux limits than the IRAS sky survey. We have obtained broad-band photometry for a large sample of quasars as part of a U.S. ISO Key Project.

The sample consists of 72 quasars observed with the ISOPHOT instrument in the following bands: 5, 7, 12, 25, 60, 100, 135, and 200 microns. Ninety percent of the quasars in the sample have redshifts less than 1, while the remaining 10% lie in the range 2 < z < 4.7. More than half of the sample consists of luminous X-ray sources, 25% are strong UV emitters, and smaller subgroups contain strong infrared sources, X-ray-quiet objects, red quasars, and BALs.

The majority of the targets, 53, were observed in chopped mode. We also have raster map data for 37 quasars, including 18 from the chopped group. Initial batch processing of the chopped data revealed that the fluxes for the brighter objects are generally consistent with IRAS values, although there are systematic differences at 60 um and 100 um. We are exploring a variety of techniques for determining the source flux and detection probability, uncertainties, systematic flux errors, and sky brightness variations. We will present a comprehensive overview of the sample using the most current analysis procedures and discuss any areas where future improvements are likely to be forthcoming. The large number of objects, wide wavelength coverage, and overlap between chopped and raster observing modes makes this sample a useful testbed for comparing observation and reduction techniques and checking the ISO flux calibrations against those from other infrared satellites.

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