ROSAT X-Ray Spectra of Quasars with a Range of Continuum Properties and Redshift
Abstract
Soft x-ray spectral observations of three targeted and two serendipitous quasars with the Rosat Position Sensitive Proportional Counter (PSPC) are reported. These quasars were observed as part of a program to observe objects covering the full range of the quasar population to study the range and evolution of their x-ray spectra and eventually their full wavelength distributions. The inital sample included three radio loud, all with z greater than 0.5 and two low redshift, radio quiet quasars, one with a known excess from Einstein observations. The highest redshift object (PKS0438-43, z = 2.85) is the first high luminosity quasar to show a significant absorbing column in excess of the Galactic value and calls into question the inverse absorption/luminosity correlation found at low redshift. Only two of the three radio loud quasars follow the Einstein observed correlation between x-ray slope and core dominance parameter.
- Publication:
-
X-ray Emission from Active Galactic Nuclei and the Cosmic X-ray Background
- Pub Date:
- March 1992
- Bibcode:
- 1992xrea.conf..210W
- Keywords:
-
- Quasars;
- Red Shift;
- Rosat Mission;
- Spectrum Analysis;
- X Ray Spectra;
- Absorption Spectra;
- Luminosity;
- Proportional Counters;
- Wavelengths;
- X Ray Astronomy;
- Astronomy