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Extending the X-ray luminosity function of AGN to high redshift

J. Silverman·P. Green·W. Barkhouse·R. Cameron·M. Kim·D. -W. Kim·B. Wilkes·G. Hasinger·the full ChaMP team
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Abstract

X-ray surveys of the extragalactic universe are now able to detect significant numbers of AGN out to high redshift (z~5). We highlight some results from the Chandra Multiwavelength Project (ChaMP) to measure the X-ray luminosity function out to these early epochs. At z > 3, we show that the comoving space density of luminous (log Lx > 44.5) AGN has a behavior similar to the optical QSO luminosity function. With a newly compiled sample of AGN from ChaMP supplemented with those from additional surveys including the Chandra Deep fields, we present a preliminary measure of the luminosity function in the hard (2-8 keV) band. With 37 AGN at z > 3, we continue to see a decline in the space density at high redshift over a wider range in luminosity. We discuss the need to identify a larger sample of obscured AGN at high redshift to determine if an early epoch of hidden supermassive black hole growth occurred.

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J. Silverman, P. Green, W. Barkhouse, R. Cameron, M. Kim, D. -W. Kim, B. Wilkes, G. Hasinger, the full ChaMP team. 2005-11-18. Extending the X-ray luminosity function of AGN to high redshift. https://arxiv.org/abs/astro-ph/0511552

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