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ChandraLarge-AreaSynopticX-RaySurveyOptical&IRCatalog

Published by High Energy Astrophysics Science Archive Research Center | National Aeronautics and Space Administration | Metadata Last Checked: October 20, 2025 | Last Modified: 2025-09-10
This table contains the redshift catalog for the X-ray sources detected in the Chandra Large Area Synoptic X-ray Survey (CLASXS). The catalog for the CLASXS field includes redshifts from previous work. The authors have extended the redshift information for the full sample using photometric redshifts. The goal of the OPTX Project is to use this survey, together with the Chandra Deep Field-North (CDF-N) and the Chandra Lockman Area North Survey (CLANS), which are among the most spectroscopically complete surveys to date, to analyze the effect of spectral type on the shape and evolution of the X-ray luminosity functions and to compare the optical spectral types with the X-ray spectral properties. The CLANS and CLASXS surveys bridge the gap between the ultra-deep pencil-beam surveys, such as the Chandra Deep Fields, and the shallower, very large-area surveys. As a result, they probe the X-ray sources that contribute the bulk of the 2-8 keV X-ray background and cover the flux range of the observed break in the log N - log S distribution. This table also contains updated optical and infrared photometric catalogs for the X-ray sources in the CLASXS field. Note that for any source with both CFHT and Subaru data in the R and z' bands, the authors used the CFHT magnitude. Typical photometric uncertainties are given in Section 3.6 of the reference paper (Trouille et al. 2008). The X-ray information for the CLASXS catalog which was published in Yang et al. (2004, AJ, 128, 1501) is available as the HEASARC CLASXS table. This table was created by the HEASARC in January 2009 based on the electronic version of Table 12 from the paper which was obtained from the ApJ web site. This is a service provided by NASA HEASARC .

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