RE-1034+39 - A HIGH-STATE SEYFERT-GALAXY

Citation
Ka. Pounds et al., RE-1034+39 - A HIGH-STATE SEYFERT-GALAXY, Monthly Notices of the Royal Astronomical Society, 277(1), 1995, pp. 5-10
Citations number
41
Categorie Soggetti
Astronomy & Astrophysics
ISSN journal
00358711
Volume
277
Issue
1
Year of publication
1995
Pages
5 - 10
Database
ISI
SICI code
0035-8711(1995)277:1<5:R-AHS>2.0.ZU;2-O
Abstract
The dominant X-ray emission of Seyfert galaxies has the form of a powe r law of mean photon index 1.9-2.0 which extends to at least 100 keV. However, recent observations, primarily from ROSAT, have revealed a su bset of Seyfert galaxies with a qualitatively different X-ray appearan ce and unusual optical spectra. RE 1034 + 39, first identified in the ROSAT EUV survey, may be a prototype of this class of AGN. ROSAT and A SCA X-ray spectra are reported here, showing RE 1034 + 39 to have inte nse soft X-ray emission, together with an unusually steep 2-10 keV pow er law of photon index similar to 2.6, with possibly some contribution from ionized reflection. We speculate that an unusually high accretio n rate is causing the intense soft X-ray flux, which - in turn - is Co mpton cooling the hard photon source, giving the observed steep spectr um at higher energies, The strong soft X-radiation may also be ionizin g the disc and inhibiting the formation of the optical broad-line clou ds. We point out the similarity of RE 1034 + 39 to the 'high'-state sp ectra from the Galactic black hole candidate binary systems such as Cy g X-1.