GINGA Observations of the X-Ray Spectra of Active Galactic Nuclei / AGN
Abstract
Ginga obtained X-ray spectra in the 1.5 to 37 keV range from several tens of Active Galactic Nuclei (AGNs). The mean spectral slope of those AGNs is steeper than that of the cosmic X-ray background. Seyfert galaxies and possibly radio-quiet quasars generally exhibit iron emission lines with equivalent widths of 100 to 200 eV. Such a large equivalent width of the fluorescent line, together with a shallow and broad absorption feature above the iron K-edge energy, can be interpreted by considering an optically thick accretion disk as a reprocessor of X-rays from a central source.
- Publication:
-
Two Topics in X-Ray Astronomy, Volume 1: X Ray Binaries. Volume 2: AGN and the X Ray Background
- Pub Date:
- November 1989
- Bibcode:
- 1989ESASP.296..783I
- Keywords:
-
- Active Galactic Nuclei;
- Ginga Satellite;
- Japanese Space Program;
- Satellite Observation;
- X Ray Spectra;
- Accretion Disks;
- Black Holes (Astronomy);
- Emission Spectra;
- Fluorescence;
- Galactic Radiation;
- Iron;
- K Lines;
- Seyfert Galaxies;
- Astronomy