ROSAT observations of radio-loud AGN.
Abstract
The authors have analysed the ROSAT soft X-ray spectra of a sample of radio loud AGN from the public archive. Based on the catalogues of Véron-Cetty and Véron (1993), Hewitt and Burbidge (1993), Stickel et al. (1994) and the NED database the sample was selected by the following criteria: radio loudness (αro > 0.4), radio flux S5 GHz ≥ 0.5 Jy, position within 55' of the center of FOV in pointed ROSAT PSPC observations. The authors' sample comprises 165 detected radio loud AGN (including 6 AGN without known redshift). It contains 98 FSQ (radio flat spectrum quasars with αr < 0.5), 35 SSQ (radio steep spectrum quasars with αr > 0.5) and 32 BL Lac objects. It is found that the FSQ have flatter spectra than the SSQ and BL Lac in the ROSAT energy range (0.1-2.4 keV). No difference between these classes is found in αro and αox. The ROSAT spectra of radio loud and radio quiet quasars are steeper than the spectra measured at higher energies (>1 keV) by Einstein, EXOSAT or Ginga.
- Publication:
-
Roentgenstrahlung from the Universe
- Pub Date:
- February 1996
- Bibcode:
- 1996rftu.proc..503R
- Keywords:
-
- X-Ray Spectra: Active Galactic Nuclei;
- X-Ray Spectra: Quasars