[Previous] | [Session 11] | [Next]
H. Ghosh, B.J. Wilkes (Harvard-Smithsonian CfA), R.M. Cutri (IPAC), G. Risaliti (Harvard-Smithsonian CfA & Arcetri Observatory), D.C. Hines (Steward Obs.), B. Nelson (IPAC), G.D. Schmidt, P. S. Smith (Steward Obs.)
The Two Micron All Sky Survey has provided a large sample of previously unknown, low-redshift (median z~.25), luminous, red, predominantly broad-line active galactic nuclei, at a sky density of ~.5 deg-2. Chandra observations of a well-defined subset show them to be x-ray faint and hard relative to other broad-line AGN. The x-ray hardness ratios suggest a wide range of intrinsic column densities, and their optical spectra show they are mostly intermediate between Type 1 and Type 2 AGN. Given what we know of their x-ray properties and adding optical spectra and polarimetric data, we extrapolate their observed characteristics both to the local universe and to high redshift. We thus investigate local counterparts to these objects, possible similar sources found in current x-ray surveys, and at the other extreme estimate the contribution to the cosmic x-ray background from this hitherto unaccounted-for population of absorbed AGN.
[Previous] | [Session 11] | [Next]
Bulletin of the American Astronomical Society, 34, #4
© 2002. The American Astronomical Soceity.