Short term variability (and a characteristic time-scale?) in the X-ray emission of active galaxies.
Abstract
Observations taken by the Ariel V Sky Survey Instrument over a five year period were used to study the variability of X-ray emission from 31 active galaxies. The investigation indicated a variability by a factor of about two on a time scale of less than or equal to one year in about 50 percent of the sources. X-ray flux variations on a time-scale of 0.5-5 days were also found for a number of sources. These variations were sometimes in the form of short outbursts with an implied 2-10 keV energy content of 10 to the 47th - 10 to the 50th erg. No clear distinction was found in the X-ray variability of active galaxies with different morphologies and X-ray luminosities. It is concluded that one day may be the characteristic timescale in the X-ray emission from a wide range of active galaxies.
- Publication:
-
Variability in Stars and Galaxies
- Pub Date:
- 1980
- Bibcode:
- 1980vasg.meet...C5P
- Keywords:
-
- Active Galaxies;
- Emission Spectra;
- Galactic Radiation;
- Periodic Variations;
- Seyfert Galaxies;
- X Ray Astronomy;
- X Ray Spectra;
- Ariel 5 Satellite;
- Astronomical Models;
- Black Holes (Astronomy);
- Galactic Nuclei;
- Galactic Structure;
- Light Curve;
- Line Spectra;
- Luminosity;
- Quasars;
- Red Shift;
- Sky Surveys (Astronomy);
- Astronomy;
- Active Galaxies:X Rays;
- Black Holes:Galactic Nuclei;
- X-Ray Sources:Variations