A Comparative Study of Soft X-Ray QSO Spectra
Abstract
A method developed to estimate spectral parameters from hardness ratios and thus to be used to study the spectral properties of a large sample of Quasi-Stellar Objects (QSO) detected in the Rosat all sky survey, is presented. The slopes of quasar spectra with low intrinsic absorption were considered as a function of the quasar redshifts. A flattening of the spectral index with increasing redshift was found and interpreted as steepening of the intrinsic spectra towards the soft X-ray region.
- Publication:
-
X-ray Emission from Active Galactic Nuclei and the Cosmic X-ray Background
- Pub Date:
- March 1992
- Bibcode:
- 1992xrea.conf..195S
- Keywords:
-
- Quasars;
- Rosat Mission;
- X Ray Spectra;
- Comparison;
- Red Shift;
- Sky Surveys (Astronomy);
- Spectrum Analysis;
- X Ray Astronomy;
- Astronomy