INTEGRAL observations of AGN obscured by the Galactic Plane

M. Molina; A. Malizia; L. Bassani; A. J. Bird; A. J. Dean; R. Landi; A. De Rosa; R. Walter; E. J. Barlow; D. J. Clark; A. B. Hill; V. Sguera

doi:10.1111/j.1365-2966.2006.10715.x

arXiv · astro-ph/0606488

INTEGRAL observations of AGN obscured by the Galactic Plane

M. Molina·A. Malizia·L. Bassani·A. J. Bird·A. J. Dean·R. Landi·A. De Rosa·R. Walter·E. J. Barlow·D. J. Clark·A. B. Hill·V. Sguera

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Abstract

In this paper we present INTEGRAL observations of 7 AGNs: two newly discovered type 1 Seyferts, IGR J18027-1455 and IGR J21247+5058, and five well known Seyferts, NGC 6814 (type 1.5), Cyg A (Type 2), MCG-05-23-16 (type 2), ESO 103-G035 (type2) and GRS1734-292. For IGR J18027-1455 and IGR J21247+5058 only INTEGRAL/IBIS data were available, while broadband spectra are presented and discussed for the remaining 5 sources for which either BeppoSAX or ASCA data were used in conjunction with INTEGRAL measurements. In the cases of NGC 6814 and GRS 1734-292, data taken in different periods indicate variability in the flux: in the case of NGC 6814 by a factor of 16 over a period of about 10 years. Although limited in size, our sample can be used to investigate the parameter space of both the photon index and cut-off energy. The mean photon index is 1.8, while the cut-off energy ranges from 30-50 keV to greater than 200 keV; in the particular case of MCG-05-23-16, ESO 103-G035 and GRS 1734-292 the cut-off energy is well constrained at or below 100 keV. We have also tested an enlarged sample, which includes INTEGRAL data of 3 more AGNs, against the correlation found by a number of authors between the photon index and the cut-off energy but have found no evidence for a relation between these two parameters. Our analysis indicates that there is a diversity in cut-off energies in the primary continuum of Seyfert galaxies.

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M. Molina, A. Malizia, L. Bassani, A. J. Bird, A. J. Dean, R. Landi, A. De Rosa, R. Walter, E. J. Barlow, D. J. Clark, A. B. Hill, V. Sguera. 2006-06-27. INTEGRAL observations of AGN obscured by the Galactic Plane. https://doi.org/10.1111/j.1365-2966.2006.10715.x

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