The extended Chandra deep field-south survey : Chandra point-source catalogs.

Abstract

We present Chandra 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 deg2, which flank the existing ≈1 Ms Chandra Deep Field–South (CDF‐S). The survey reaches sensitivity limits of ≈ and ≈ ergs cm−2 s−1 for the 0.5–2.0 and 2–8 keV bands, respectively. We detect 762 distinct X‐ray point sources 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 ≈035. 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 our main Chandra catalog, we constructed a supplementary source catalog containing 33 lower significance X‐ray point sources that have bright optical counterparts (R < 23). These sources generally have X‐ray–to–optical flux ratios expected for normal and starburst galaxies, which lack a strong AGN component. We present basic number‐count results for our main Chandra catalog and find good agreement with the ≈1 Ms CDF‐S for sources with 0.5–2.0 and 2–8 keV fluxes greater than and ergs cm−2 s−1, respectively. Furthermore, three extended sources are detected in the 0.5–2.0 keV band, which are found to be likely associated with galaxy groups or poor clusters at ; these have typical rest‐frame 0.5–2.0 keV luminosities of ergs s−1.