Demography of High-Redshift AGN

• Main Authors: Fabrizio Fiore, Simonetta Puccetti, Smita Mathur
• Format: Article
• Language: English
• Published: Hindawi Limited 2012-01-01
• Series: Advances in Astronomy
• Online Access: http://dx.doi.org/10.1155/2012/271502

High-redshift AGN holds the key to understanding early structure formation and to probe the Universe during its infancy. We review the latest searches for high-z AGN in the deepest X-ray field so far, the Chandra Deep Field South (CDFS) 4 Msecond exposure. We do not confirm the positive detection of a signal in the stacked Chandra images at the position of z~6 galaxies recently reported by Treister and collaborators (2011). We present z>3 X-ray sources number counts in the 0.5–2 keV band, obtained joining CDFS faint detections (see Fiore et al. (2011)), with Chandra-COSMOS and XMM-COSMOS detections. We use these number counts to make predictions for surveys with three mission concepts: Athena, WFXT, and a Super-Chandra.