Cosmic gamma rays from active galactic nuclei
Abstract
We have used the SAS-2 γ-ray data to search for γ-rays of energy >100 MeV from extragalactic active galactic nuclei (AGNs). The correlation function devised by the COS-B group to search for galactic γ-ray sources has been used. We have identified 18 such AGNs, including 13 quasars, 3 BL Lac objects, 1 Seyfert galaxy and 1 radiogalaxy. We have further investigated the relationship between the γ-ray fluxes in the energy regions > 100 MeV and 35-100 MeV and their redshifts, and we have also derived their γ-ray spectral indices. The results give further support to our claim that the sources detected are genuine extragalactic objects.
- Publication:
-
Vistas in Astronomy
- Pub Date:
- 1988
- DOI:
- 10.1016/0083-6656(88)90270-X
- Bibcode:
- 1988VA.....31..579Y
- Keywords:
-
- Active Galactic Nuclei;
- Galactic Cosmic Rays;
- Gamma Ray Astronomy;
- X Ray Sources;
- Bl Lacertae Objects;
- Cross Correlation;
- Point Spread Functions;
- Quasars;
- Radio Galaxies;
- Seyfert Galaxies;
- Space Radiation