Searcharxiv⌕ Search

arXiv subjects

the CDFS Team

Publications and source records attributed to the CDFS Team.

2 recordsLinked to original sources
arXiv2006

AGN and Galaxy evolution from Deep X-ray surveys

Deep X-ray surveys are providing crucial information on the evolution of AGN and galaxies. We review some of the latest results based on the X-ray spectral analysis of the sources detected in the Chandra Deep Field South, namely: i) constraints on obscured accretion; ii) constraints on the missing fraction of the X-ray background; iii) the redshift distribution of Compton-thick sources and TypeII QSO; iv) the detection of star formation activity in high-z galaxies through stacking techniques; v) the detection of large scale structure in the AGN distribution and its effect on nuclear activity. Such observational findings are consistent with a scenario where nuclear activity and star formation processes develop together in an anti-hierarchical fashion.

astro-ph↗
arXiv2001

Agns and Clusters in Chandra Deep Fields

The Chandra X-ray Satellite already observed several deep fields, including the two 1 Megasec exposures of the Chandra Deep Field South (CDFS) and North. We review here the main findings from the CDFS. The LogN-LogS relations show the resolution of the X-ray background into point sources at the level of 83-99% in the 1-2 keV band and 65-98% in the 2-10 keV band, given the uncertainties in the unresolved value. The so called ``spectral paradox'' is solved by a hard, faint population of sources constituted mostly by nearby (z<1) absorbed (Type II) AGNs with hard-band luminosities L~10^{42}-10^{44} erg/s. When comparing these results to other deep fields in the X-ray band, we find that the AGNs detected in 0.1 deg^2 of the CDFS are representative of the AGNs population as a whole. However, we also noticed an excess in the hard counts in two Chandra deep fields. If we include this excess and average it among the observed fields, the total contribution of the XRB can grow of about 7%. Finally, we discuss briefly the properties of the Intra Cluster Medium imaged at high z, showing no evolution in clusters properties up to z~1.

astro-ph↗