We present results of the analysis of 112 X-ray-selected and fully optically-identified quasars in four sky fields in the southern hemisphere, detected by the Rosat Position Sensitive Proportional Counters. These fields were originally studied for the ultraviolet-excess properties of objects in the fields. This is one of the largest sets of fully-identified Rosat-observed quasars. We determine the quasars' power-law spectral index alpha_E with three different methods: spectral ``stacking'', hardness ratios, and direct fitting, and discuss the differences between each of these methods. We derive monochromatic X-ray and optical luminosities L_x and Lopt and discuss the relationship between them, examine the optical-X-ray spectral slope alpha_ox and the related L_x/Lopt ratio and their relationship to redshift, L_x, and Lopt, and finally present a model which could explain the observations.
American Astronomical Society Meeting Abstracts
- Pub Date:
- December 1994