X-ray, optical, and radio properties of quasars.
Abstract
A sample of 26 low-redshift quasars was examined for relationships between X-ray luminosity and optical spectroscopic features; all quasars were observed with the Einstein Observatory and with the IDS on the Lick 3 meter telescope. Evidence is found for correlations between quasar X-ray luminosity and both optical continuum luminosity and H-beta luminosity. In the latter case, there is a smooth relationship connecting quasars, Seyfert 1, and Seyfert 2 galaxies. For the quasars in this sample, there is also a strong correlation between optical continuum luminosity and both the H-beta luminosity and equivalent width. Evidence is also found for a weak correlation between alpha-prime (ox), the mean continuum spectral index between 5000 A and 2 keV, and Fe II equivalent width, H-beta equivalent width, H-beta line width at zero intensity, and the ratio of H-beta equivalent width to its line width at zero intensity.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 1982
- DOI:
- 10.1086/160007
- Bibcode:
- 1982ApJ...257..499B
- Keywords:
-
- Astronomical Spectroscopy;
- Luminosity;
- Quasars;
- Radio Spectra;
- Red Shift;
- X Ray Sources;
- Emission Spectra;
- Galactic Nuclei;
- H Beta Line;
- Light Emission;
- Seyfert Galaxies;
- Spectral Line Width;
- Astrophysics