The density and masses of obscured Black Holes

Andrea Comastri; Fabrizio Fiore

doi:10.1007/s10509-004-4023-5

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arXiv · astro-ph/0404047

The density and masses of obscured Black Holes

Andrea Comastri·Fabrizio Fiore

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Abstract

Recent Chandra and XMM-Newton surveys have uncovered a large fraction of the obscured AGN responsible of the hard X-ray background. One of the most intriguing results of extensive programs of follow-up observations concerns the optical and near-infrared properties of the hard X-ray sources counterparts. More specifically, for a significant fraction of hard X-ray obscured sources the AGN responsible of the high X-ray luminosity remains elusive over a wide range of wavelengths from soft X-rays to near-infrared. This very observational result opens the possibility to investigate the host of bright obscured quasars in some detail. Here we briefly report on some preliminar results obtained for a small sample of elusive AGN in the HELLAS2XMM survey.

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BibTeX RIS

Andrea Comastri, Fabrizio Fiore. 2004-04-02. The density and masses of obscured Black Holes. https://doi.org/10.1007/s10509-004-4023-5

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