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The Chandra Deep Field-North Survey. XIII. 2 Ms Point-Source Catalogs

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 نشر من قبل D. M. Alexander
 تاريخ النشر 2003
  مجال البحث فيزياء
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We present catalogs for the ~2 Ms Chandra Deep Field-North, currently the deepest X-ray observation of the Universe in the 0.5-8.0 keV band. Five hundred and three (503) X-ray sources are detected over an ~448 sq.arcmin area in up to seven bands; 20 of these X-ray sources lie in the Hubble Deep Field-North. Source positions are determined using matched-filter and centroiding techniques; the median positional uncertainty is ~0.3 arcsecs. The X-ray colors of the detected sources indicate a broad variety of source types, although absorbed AGNs (including some possible Compton-thick sources) are clearly the dominant type. We also match lower significance X-ray sources to optical counterparts and provide a list of 79 optically bright R<~23) lower significance Chandra sources. The majority of these sources appear to be starburst and normal galaxies. We investigate the source-free background, determine the maximum photon-limited exposures, and investigate source confusion. These analyses directly show that Chandra can achieve significantly higher sensitivities in an efficient nearly photon-limited manner and be largely free of source confusion. To allow consistent comparisons, we have also produced point-source catalogs for the ~1 Ms Chandra Deep Field-South (CDF-S). Three hundred and twenty-six (326) X-ray sources are included in the main Chandra catalog, and an additional 42 optically bright X-ray sources are included in a lower significance Chandra catalog. We find good agreement with the photometry of the previously published CDF-S catalogs; however, we provide significantly improved positional accuracy (ABRIDGED).



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