The Galaxy Evolution Explorer (GALEX) Source Catalogs
Abstract
We present the Galaxy Evolution Explorer (GALEX) All-Sky Survey Source Catalog (GASC) and the GALEX Medium Imaging Survey Source Catalog (GMSC) derived from the GALEX GR6 data release. These catalogs provide vetted and unique measurements of point and extended sources up to 1 arcminute diameter in the GALEX NUV (2300 Angstroms) and FUV (1500 Angstroms) bands. A principal goal for the project is to ensure that the research community has access to high quality measurements of the enormous volume of GALEX imaging data. Our intention is that the catalogs will serve as the official GALEX reference for cross matching to other surveys such as WISE, SDSS, and 2MASS. The GASC and GMSC are defined by NUV detections, which typically have significantly higher S/N than the FUV. The GASC and GMSC report FUV fluxes within NUV defined apertures for those regions with FUV observations. Covering a total of 26,300 deg2 of sky, the GASC consists of all GALEX observations with exposure times below 800 sec and reaches a depth of NUV 21 (AB mag). The GMSC covers a smaller region of 5000 deg2 with exposure times between 800 and 10,000 sec and reaches a depth of NUV 23 mag. There are a total of 40 million unique sources in the GASC and 22 million in the GMSC. Each catalog is accompanied by exposure time, coverage and flag maps in FITS and Healpix formats. We have also quantified the completeness, reliability, and astrometric uncertainties of both catalogs. Users will be able to access the catalogs through the Multi-mission Archive at the Space Telescope Science Institute (MAST) and eventually through the NASA Extragalactic Database. The images and footprint files will be made available from MAST as well.
- Publication:
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American Astronomical Society Meeting Abstracts #219
- Pub Date:
- January 2012
- Bibcode:
- 2012AAS...21934001S