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arXiv · 1109.2888

Faint high-redshift AGN in the Chandra Deep Field South: the evolution of the AGN luminosity function and black hole demography

F. Fiore·S. Puccetti·A. Grazian·N. Menci·F. Shankar·P. Santini·E. Piconcelli·A. M. Koekemoer·A. Fontana·K. Boutsia·M. Castellano·A. Lamastra·C. Malacaria·C. Feruglio·S. Mathur·N. Miller·M. Pannella
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Abstract

We present detection and analysis of faint X-ray sources in the Chandra deep field south (CDFS) using the 4 Msec Chandra observation and adopting a new detection algorithm, based on a targeted search at the position of known high-z galaxies. This optimized technique results in the identification of 54 z>3 AGNs, 29 of which are new detections. Applying stringent completeness criteria, we derive AGN luminosity functions in the redshift bins 3-4, 4-5 and >5.8 and for 42.75 3 (18+17-10%). Their optical counterparts are not strongly reddened and we thus conclude that the size of the X-ray absorber is likely smaller than the dust sublimation radius. We finally report the discovery of a highly star-forming galaxy at z=3.47. If confirmed, this would be one of the farthest objects in which stellar sources are detected in X-rays.

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F. Fiore, S. Puccetti, A. Grazian, N. Menci, F. Shankar, P. Santini, E. Piconcelli, A. M. Koekemoer, A. Fontana, K. Boutsia, M. Castellano, A. Lamastra, C. Malacaria, C. Feruglio, S. Mathur, N. Miller, M. Pannella. 2011-09-13. Faint high-redshift AGN in the Chandra Deep Field South: the evolution of the AGN luminosity function and black hole demography. https://doi.org/10.1051/0004-6361/201117581

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