Quasar Energy Distributions. I. Soft X-Ray Spectra of Quasars
Abstract
As the initial stage of a study of quasar energy distributions (QEDs), Einstein IPC spectra of 24 quasars are presented. These are combined with previously reported IPC spectra to form a sample of 33 quasars with well-determined soft X-ray slopes. A correlation analysis shows that radio loudness, rather than redshift or luminosity, is fundamentally related to the X-ray slope. This correlation is not followed by higher energy spectra of active galaxies. Two components are required to explain both sets of results. The best-fit column densities are systematically smaller than the Galactic values. The same effect is not present in a sample of BL Lac objects, implying that the effect is intrinsic to the quasars and is caused by a low-energy turnup in the quasar spectra.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 1987
- DOI:
- Bibcode:
- 1987ApJ...323..243W
- Keywords:
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- Astronomical Spectroscopy;
- Quasars;
- Spectral Energy Distribution;
- X Ray Spectra;
- Bl Lacertae Objects;
- Radio Spectra;
- Red Shift;
- Stellar Luminosity;
- Astrophysics;
- BL LACERTAE OBJECTS;
- QUASARS;
- SPECTROPHOTOMETRY;
- X-RAYS: SPECTRA