INTEGRAL/IBIS Extragalactic survey: 20-100 keV selected AGN
/ Authors
L. Bassani, M. Molina, A. Malizia, J. Stephen, A. Bird, A. Bazzano, G. Belanger, A. Dean, A. Rosa, P. Laurent
and 3 more authors
/ 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 ∼ 1.5 × 10 − 11 erg cm − 2 s − 1 . 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.
DOI: 10.1086/500132