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Description
Nuclear obscuration plays a key role in the initial phases of AGN growth, yet not many highly obscured AGN are currently known beyond the local Universe, and their search is an active topic of research. The XMM-Newton survey in the Chandra Deep Field South (XMM-CDFS) aims at detecting and studying the spectral properties of a significant number of obscured and Compton-thick (N<sub>H</sub> >= 10<sup>24</sup> cm<sup>-2</sup>) AGN. The large effective area of XMM-Newton in the 2-10 and 5-10 keV bands, coupled with a 3.45-Ms nominal exposure time (2.82 and 2.45 Ms after lightcurve cleaning for MOS and PN respectively), allows the authors to build clean samples in both bands, and makes the XMM-CDFS the deepest XMM-Newton survey currently published in the 5-10 keV band. The large multi-wavelength and spectroscopic coverage of the CDFS area allows for an immediate and abundant scientific return. In this paper, the authors present the data reduction of the XMM-CDFS observations, the method for source detection in the 2-10 and 5-10 keV bands, and the resulting catalogs. A number of 339 and 137 sources are listed in the above bands with flux limits of 6.6 x 10<sup>-16</sup> and 9.5 x 10<sup>-16</sup> erg/s/cm<sup>2</sup>, respectively. The flux limits at 50% of the maximum sky coverage are 1.8 x 10<sup>-15</sup> and 4.0 x 10<sup>-15</sup> erg/s/cm<sup>2</sup>, respectively. The catalogs have been cross-correlated with the Chandra ones: 315 and 130 identifications have been found with a likelihood-ratio method, respectively. 15 new sources, previously undetected by Chandra, have been found; 5 of them lie in the 4-Ms area. Redshifts, either spectroscopic or photometric, are available for ~92% of the sources. The number counts in both bands are presented and compared to other works. The survey coverage has been calculated with the help of two extensive sets of simulations, one set per band. The simulations have been produced with a newly-developed simulator, written with the aim of the most careful reproduction of the background spatial properties. For this reason, the authors present a detailed decomposition of the XMM-Newton background into its components: cosmic, particle, and residual soft protons. The three components have different spatial distributions. The importance of these three components depends on the band and on the camera; the particle background is the most important one (80-90% of the background counts), followed by the soft protons (4-20%). X-ray sources were detected in the 3-Ms XMM-Newton observations of the Chandra Deep Field South. Source detection was done in two steps, first using the PWXDetect software, and then using emldetect. 339 Sources detected by both programs are presented in the main tables, while 74 sources only detected by PWXDetect are presented in the supplementary tables. The 2-10 and 5-10 keV bands were analyzed separately. This HEASARC table contains the main sample of 339 sources detected in the 2-10 keV band in the XMM-CDFS survey. (The table of 5-10 keV XMM-CDFS sources is also available at the HEASARC as the XMMCDFS510 table). This table does not include the 74 supplementary sources which were detected only with PWXDetect. These supplementary sources were on average detected at low significance; many of them were on the borders of the FOV; and a few were in crowded fields where EMLDetect had trouble separating the different PSF components. Nevertheless, 4 of these sources were bright enough that a spectrum could be extracted. This table was created by the HEASARC in September 2013 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/555/A42">CDS Catalog J/A+A/555/A42</a> files main210.dat and notes210.dat. This is a service provided by NASA HEASARC .
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