The AGN content of hard X-ray surveys

A. Comastri; C. Vignali; M. Brusa

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arXiv · astro-ph/0112293

The AGN content of hard X-ray surveys

A. Comastri·C. Vignali·M. Brusa

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Abstract

Multiwavelength observations of the hard X-ray selected sources discovered by BeppoSAX, Chandra and XMM-Newton surveys have significantly improved our knowledge of the AGN population. The increasing number of X-ray obscured AGN so far discovered confirms the prediction of those AGN synthesis models for the X-ray background based on the Unified scheme. However, follow-up optical observations of hard X-ray selected sources indicate that their optical properties are quite varied and the simple relations between optical and X-ray absorption are by no means without exception. Moreover, there is evidence of a substantial number of luminous X-ray sources hosted by apparently normal galaxies. In this paper the results obtained from multiwavelength observations of hard X-ray selected sources discovered by BeppoSAX and XMM-Newton are presented and briefly discussed.

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A. Comastri, C. Vignali, M. Brusa. 2001-12-12. The AGN content of hard X-ray surveys. https://arxiv.org/abs/astro-ph/0112293

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