Chandra Deep Field South 2-Megasecond Catalog

This table contains point-source catalogs for the ~2 Ms exposure of the Chandra Deep Field-South (CDF-S) this is one of the two most sensitive X-ray surveys ever performed. The survey covers an area of ~436 arcmin&lt;sup&gt;2&lt;/sup&gt; and reaches on-axis sensitivity limits of ~1.9 x 10&lt;sup&gt;-17&lt;/sup&gt; and ~1.3 x 10&lt;sup&gt;-16&lt;/sup&gt; erg cm&lt;sup&gt;-2&lt;/sup&gt; s&lt;sup&gt;-1&lt;/sup&gt; for the 0.5-2.0 and 2-8 keV bands, respectively. Four hundred and sixty-two X-ray point sources (source_sample = &#39;Main CDF-S&#39; in this table) are detected in at least one of three X-ray bands that were searched; 135 of these sources are new compared to the previous ~1 Ms CDF-S detections. Source positions are determined using centroid and matched-filter techniques; the median positional uncertainty is ~0.36&quot;. The X-ray-to-optical flux ratios of the newly detected sources indicate a variety of source types; ~55% of them appear to be active galactic nuclei, while ~45% appear to be starburst and normal galaxies. This table contains, in addition to the main Chandra catalog, the supplementary catalog of 86 X-ray sources (source_sample = &#39;CDF-S + E-CDF-S&#39; in this table) in the ~2 Ms CDF-S footprint that was created by merging the ~250 ks Extended Chandra Deep Field-South with the CDF-S; this approach provides additional sensitivity in the outer portions of the CDF-S. This table also contains a second supplementary catalog (source_sample = &#39;Optically Bright&#39; in this table) of 30 X-ray sources which was constructed by matching lower significance X-ray sources to bright optical counterparts (R &lt; 23.8); the majority of these sources appear to be starburst and normal galaxies. The total number of sources in this table, which contains the main and 2 supplementary catalogs, is thus 578. Optical R-band counterparts and basic optical and infrared photometry are provided for the X-ray sources in the main and supplementary catalogs. The authors also include existing spectroscopic redshifts for 224 of the X-ray sources. The average backgrounds in the 0.5-2.0 and 2-8 keV bands are 0.066 and 0.167 counts Ms&lt;sup&gt;-1&lt;/sup&gt; pixel&lt;sup&gt;-1&lt;/sup&gt;, respectively, and the background counts follow Poisson distributions. The effective exposure times and sensitivity limits of the CDF-S are now comparable to those of the ~2 Ms Chandra Deep Field-North (CDF-N). In their paper, the authors also present cumulative number counts for the main catalog and compare the results to those for the CDF-N. The soft-band number counts for these two fields agree well with each other at fluxes higher than ~2 x 10&lt;sup&gt;-16&lt;/sup&gt; erg cm&lt;sup&gt;-2&lt;/sup&gt; s&lt;sup&gt;-1&lt;/sup&gt;, while the CDF-S number counts are up to ~25% smaller than those for the CDF-N at fluxes below ~2 x 10&lt;sup&gt;-16&lt;/sup&gt; erg cm&lt;sup&gt;-2&lt;/sup&gt; s&lt;sup&gt;-1&lt;/sup&gt; in the soft band and ~2 x 10&lt;sup&gt;-15&lt;/sup&gt; erg cm&lt;sup&gt;-2&lt;/sup&gt; s&lt;sup&gt;-1&lt;/sup&gt; in the hard band, suggesting small field-to-field variations. This table was created by the HEASARC in December 2008 based on the electronic version of Tables 2, 5 and 6 from the reference paper which were obtained from the ApJ web site. It was last modified by the HEASARC in July 2011. This is a service provided by NASA HEASARC .

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Organization: National Aeronautics and Space Administration