Fabian Rother(1), Hermann Brunner(2), Michael Maisack(1), Rüdiger Staubert(1)
(1)Institut für Astronomie und Astrophysik, Astronomie, Universität
Tübingen, D-72076 Tübingen, Germany
(2)Astrophysikalisches Institut Potsdam, D-14482 Potsdam, Germany
Poster presented at the Conference Röntgenstrahlung from the
Universe, Würzburg, Germany, September 25-29, 1995
to be published in the Proceedings of this Conference
Abstract. We 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 & Véron (1993), Hewitt & Burbidge (1993), Stickel et al. (1994) and the NED database the sample was selected by the following criteria:
Our sample comprises 165 detected radio loud AGN (including 6 AGN without known redshift). It contains 98 FSQ (radio flat spectrum quasars with alpha_r < 0.5), 35 SSQ (radio steep spectrum quasars with alpha_r > 0.5) and 32 BL Lac objects.
- radio loudness (alpha_ro > 0.4),
- radio flux S_5GHz > 0.5 Jy,
- position within 55' of the center of FOV in pointed ROSAT PSPC observations.
We find that the FSQ have flatter spectra than the SSQ and BL Lacs in the ROSAT energy range (0.1 - 2.4 keV). No difference between these classes is found in alpha_ro and alpha_ox. 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.
Paper (37k gzip'ed Postscript including figures)
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Jürgen Barnstedt (barnstedt AT astro.uni-tuebingen.de)
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