We present results based on the first INTEGRAL AGN catalogue. The catalogue includes 42 AGN, of which 10 are Seyfert 1, 17 are Seyfert 2, and 9 are intermediate Seyfert 1.5. The fraction of blazars is rather small with 5 detected objects, and only one galaxy cluster and no star-burst galaxies have been detected so far. The sample consists of bright (fx > 5e-12 erg/cm**2/s), low luminosity (L = 2e43 erg/s), local (z = 0.020) AGN. Although the sample is not flux limited, we find a ratio of obscured to unobscured AGN of 1.5 - 2.0, consistent with luminosity dependent unified models for AGN. Only four Compton-thick AGN are found in the sample. This implies that the missing Compton-thick AGN needed to explain the cosmic hard X-ray background would have to have lower fluxes than discovered by INTEGRAL so far.
@article{arxiv.astro-ph/0510833,
title = {Results from the First INTEGRAL AGN Catalogue},
author = {V. Beckmann and S. Soldi and C. R. Shrader and N. Gehrels},
journal= {arXiv preprint arXiv:astro-ph/0510833},
year = {2007}
}
Comments
6 pages, 5 figures, proc. of "The X-ray Universe 2005", San Lorenzo de El Escorial (Madrid, Spain), 26-30 September 2005, ESA-SP 604