Description
This table contains the combined point-source catalogs for the Extended Chandra Deep Field- South (E-CDF-S) survey. The E-CDF-S consists of four contiguous 250 ks Chandra observations covering an approximately square region of total solid angle ~0.3 square degrees, which flank the existing ~1 Ms Chandra Deep Field-South (CDF-S). The survey reaches sensitivity limits of ~1.1 x 10<sup>-16</sup> and ~6.7 x 10<sup>-16</sup> ergs cm<sup>-2</sup> s<sup>-1</sup> for the 0.5-2.0 and 2-8 keV bands, respectively. 762 distinct X-ray point sources are detected within the E-CDF-S exposure; 589 of these sources are new (i.e., not previously detected in the ~1 Ms CDF-S). This brings the total number of X-ray point sources detected in the E-CDF-S region to 915 (via the E-CDF-S and ~1 Ms CDF-S observations). Source positions are determined using matched-filter and centroiding techniques; the median positional uncertainty is ~0.35". The basic X-ray and optical properties of these sources indicate a variety of source types, although absorbed active galactic nuclei (AGNs) seem to dominate. In addition to the main Chandra catalog, this table contains the supplementary source catalog with 33 lower-significance X-ray point sources that have bright optical counterparts (R < 23 mag). These sources generally have X-ray-to-optical flux ratios expected for normal and starburst galaxies, which lack a strong AGN component. The basic number-count results for the main Chandra catalog are in good agreement with the ~1 Ms CDF-S for sources with 0.5-2.0 and 2-8 keV fluxes greater than 3 x 10<sup>-16</sup> and 1 x 10<sup>-15</sup> ergs cm<sup>-2</sup> s<sup>-1</sup>, respectively. This HEASARC table contains 809 entries: 762 entries corresponding to the 762 sources listed in the main catalog (Table 2 of the published paper), 14 sources from the cross-field source list (Table 3) which give properties for sources which were detected in more than one observational sources, e.g. there are two entries for the source with source_number = 367, one entry coming from the main catalog, the other entry from the cross-field catalog, and 33 entries corresponding to the 33 sources in the supplementary, optically bright source catalog (Table 6). The HEASARC has created a new parameter called source_type to identify from which of these 3 original tables any given entry comes from; it is set to 'main', 'crossfield' and 'supplement' for entries from Tables 2, 3, and 6, respectively. This online catalog was created by the HEASARC in January 2006 based on machine-readable versions of tables 2, 3, and 6 from the paper which were obtained from the ApJ website. This is a service provided by NASA HEASARC .
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