ARIEL-6 Medium Energy Spectral Observations of Active Galaxies
Abstract
X-ray spectra of the BL Lac type object Mkn 421 and several Seyfert type 1 galaxies; IIIZw2, MCG8-11-11 and NGC 4151, have been obtained using the Leicester University instrument on board the Ariel-6 satellite. The Mkn 421 spectrum is best represented by two powerlaw components, the soft component having α ∼ 3.4 whilst the hard flux has α ∼ 1.0. In MCG8-11-11 there is clear evidence for spectral variability between our observation in late 1979 and that of HEAO-1/A2 in 1977. The Ariel-6 spectrum of MCG8-11-11 can be fitted by a powerlaw of index α ∼ 2.1 together with an iron line at ∼ 6.2 keV with an equivalent width of ∼ 1.6 keV. The first X-ray spectrum of IIIZw2 is also presented, fitting with a powerlaw we find an index of α ∼ 1.7. With the exception of NGC 4151 there is no evidence for a significant column of cool material along the line of sight.
- Publication:
-
Space Science Reviews
- Pub Date:
- March 1981
- DOI:
- 10.1007/BF01245998
- Bibcode:
- 1981SSRv...30...47H
- Keywords:
-
- Active Galaxies;
- Ariel Satellites;
- Bl Lacertae Objects;
- Galactic Radiation;
- Seyfert Galaxies;
- X Ray Spectra;
- Line Spectra;
- Proportional Counters;
- Spectrum Analysis;
- X Ray Sources;
- Astronomy