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INTEGRAL detection of three AGN in the Cassiopeia region, including a new source IGR J02097+5222

ATel #662; L. Kuiper (SRON), W. Hermsen (SRON/University of Amsterdam), J. in 't Zand (SRON/Utrecht University) and P. R. den Hartog (SRON)
on 24 Nov 2005; 10:50 UT
Credential Certification: Lucien Kuiper (L.M.Kuiper@sron.nl)

Subjects: X-ray, Gamma Ray, AGN, Quasar

Referred to by ATel #: 665

The Cassiopeia region was observed by INTEGRAL from 2005 June 29 to July 16 for about 1 Ms. In this observation, targeted at anomalous X-ray pulsar 4U 0142+61, we discovered in IBIS ISGRI sky maps a new INTEGRAL hard X-ray (20-65 keV) source, IGR J02097+5222, at position R.A.= 02 09 45.6, Decl. = 55 22 48.0 (equinox 2000; estimated uncertainty 3 arcminute), consistent with that of 1E 0206.3+5212, a Seyfert-1 galaxy at z=0.0492. A spectral fit assuming a power-law model resulted in a photon index of 1.7+/-0.4 and a 20-65 keV flux of (9.7 +/- 1.4)E-6 ph/cm2 s keV. We also detected hard X-rays (20-45 keV) from 1ES 0033+595, a BL Lac type object at z=0.086. This confirms an earlier hard X-ray detection by the BeppoSAX PDS (Costamante et al., 2001, A&A 371, 512). A power-law fit indicates a (very) soft spectrum with photon index 3.5 +/- 1.0, in line with spectral measurements by XMM Newton (0.5-10 keV; Perlman et al., 2005, ApJ 625, 727) which clearly showed spectral softening for higher energies. The 20-45 keV photon flux is (1.1 +/- 0.2)E-5 ph/cm2 s keV. Finally, we detected significantly hard X-ray emission (20-65 keV) from QSO B0241+622 (1E 0241.0+6215), a Seyfert-1 galaxy at z=0.0446. A power-law fit yielded a photon index of 1.90 +/- 0.24 and a 20-65 keV flux of (1.26 +/- 0.11)E-5 ph/cm2 s keV.