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arXiv · astro-ph/0701675

Searching for absorbed AGN in the 2XMM-Newton pre-release EPIC Serendipitous Source Catalogue

Elisabetta Memola·Alessandro Caccianiga·Filomena Cocchia·Roberto Della Ceca·Tommaso Maccacaro·Paola Severgnini·Duncan J. Fyfe·Silvia Mateos·Mike G. Watson·Georg Lamer
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Abstract

We aim to test a method of efficiently selecting X-ray obscured AGN in the 2XMM-Newton EPIC Serendipitous Source Catalogue. By means of a strong correlation established using the XMM-Newton Hard Bright Sample between the intrinsic absorption and the hardness ratio to the 0.5-2.0 keV and 2.0-4.5 keV bands, an efficient way of selecting absorbed sources has been worked out. A hardness ratio selection based on the 2XMM-Newton pre-release Source Catalogue led us to the definition of candidates likely to be obscured in X-rays. X-ray and optical spectral analysis were performed for three objects. Strong absorption (NH > 10^{22} cm^{-2}) was detected from the X-ray analysis, confirming the efficiency of the method used to select obscured sources. The presence of absorption is also revealed in the optical band, although at a significantly lower level than inferred from the X-ray band.

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Elisabetta Memola, Alessandro Caccianiga, Filomena Cocchia, Roberto Della Ceca, Tommaso Maccacaro, Paola Severgnini, Duncan J. Fyfe, Silvia Mateos, Mike G. Watson, Georg Lamer. 2007-01-24. Searching for absorbed AGN in the 2XMM-Newton pre-release EPIC Serendipitous Source Catalogue. https://doi.org/10.1051/0004-6361%3A20066571

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