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Description
This table contains the results of a deep (about 80 ks) XMM-Newton survey of the largest sample of near-infrared-selected Extremely Red Objects (R-K > 5) available to date to K<sub>s</sub> < ~19.2. At the relatively bright X-ray fluxes ((F(2-10 keV) >~ 4 x 10<sup>-15</sup> erg cm<sup>-2</sup> s<sup>-1</sup>) and near-infrared magnitude probed by the present observations, the fraction of AGN (i.e. X-ray detected) among the ERO population is small (~3.5%); conversely, the fraction of EROs among hard X-ray selected sources is much higher (~20%). The X-ray properties of the 9 EROs detected in this XMM-Newton observation indicate absorption in excess of 10<sup>22</sup> cm<sup>-2</sup> in a large fraction of them. The X-ray, optical and near-infrared properties of those X-ray selected EROs with a spectroscopic or photometric redshift nicely match those expected for type 2 quasars, the high-luminosity, high-redshift obscured AGNs predicted in baseline XRB synthesis models. A close correlation is detected between X-ray and K-band fluxes. This table contains the X-ray and optical information for the sources detected in the sum of 3 separate XMM-Newton observations of a field centered on 14 49 25, +09 00 13 (J2000.0 RA and Dec) known as the "Daddi" field (Daddi et al. 2000, A&A, 361, 535) in which 257 EROs are known to be present. The data from all 3 EPIC instruments (PN, MOS1 and MOS2) obtained in the 3 observations was combined, yielding a total exposure time for the PN of ~82 ks, and for the MOS instruments of ~78 ks. The X-ray hardness ratio (HR) and the optical to near-infrared color (R and K magnitudes) are reported for all the detected X-ray sources and their counterparts, along with the reliability of the X-ray to optical or near-infrared associations as measured by the likelihood ratios, LR(R) and LR(K). This table lists data for the 111 proposed optical/infrared counterparts for the 97 detected X-ray sources, i.e., X-ray sources with more than one possible optical/IR counterpart will have multiple entries in this table, one for each counterpart, as follows: 73 X-ray sources have secure optical/near-IR counterparts (counterpart_status=1), 7 X-ray sources have 2 possible 'likely' counterparts, and 1 X-ray source has 3 such counterparts (counterpart_status=2), 6 X-ray sources have only low-likelihood counterparts all of which lie outside the 3" matching radii (counterpart_status=3), and the remaining 9 X-ray sources lack optical and infrared photometry (counterpart_status=4). This table was created by the HEASARC in February 2007 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/432/69">CDS Catalog J/A+A/432/69</a> files table1.dat and table2.dat. This is a service provided by NASA HEASARC .
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