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arXiv · astro-ph/0211306

Unconventional AGN in hard X-ray surveys

A. Comastri·M. Brusa·M. Mignoli·the HELLAS2XMM collaboration
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Abstract

Extensive programs of follow-up observations of hard X-ray selected sources have unambiguosly revealed that the sources of the X-ray background are characterized by an extremely large dispersion in their optical magnitude and spectroscopic classification. Here we present the results of an attempt to understand the nature of the observed variety using a simple prescription for their optical to X-ray energy distribution.

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A. Comastri, M. Brusa, M. Mignoli, the HELLAS2XMM collaboration. 2002-11-14. Unconventional AGN in hard X-ray surveys. https://doi.org/10.1002/asna.200310008

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