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INTEGRAL/IBIS Extragalactic survey: 20-100 keV selected AGN

L. Bassani·M. Molina·A. Malizia·J. B. Stephen·A. J. Bird·A. Bazzano·G. Belanger·A. J. Dean·A. De Rosa·P. Laurent·F. Lebrun·P. Ubertini·R. Walter
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Abstract

Analysis of INTEGRAL Core Program and public Open Time observations performed up to April 2005 provides a sample of 62 active galactic nuclei in the 20-100 keV band above a flux limit of ~1.5x10^-11 erg/cm2/s. Most(42) of the sources in the sample are Seyfert galaxies, almost equally divided between type 1 and 2 objects, 6 are blazars and 14 are still unclassified. Excluding the blazars, the average redshift of our sample is 0.021 while the mean luminosity is Log(L) = 43.45. We find that absorption is present in 65% of the objects with 14% of the total sample due to Compton thick active galaxies. In agreement with both Swift/BAT team results and 2-10 keV studies, the fraction of absorbed objects decreases with the 20-100 keV luminosity. All Seyfert 2s in our sample are absorbed as are 33% of Seyfert 1s. The present data highlight the capability of INTEGRAL to probe the extragalactic gamma-ray sky and to find new and/or absorbed active galaxies.

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L. Bassani, M. Molina, A. Malizia, J. B. Stephen, A. J. Bird, A. Bazzano, G. Belanger, A. J. Dean, A. De Rosa, P. Laurent, F. Lebrun, P. Ubertini, R. Walter. 2005-12-01. INTEGRAL/IBIS Extragalactic survey: 20-100 keV selected AGN. https://doi.org/10.1086/500132

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