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A Catalog of 1.4 GHz Radio Sources from the FIRST Survey

Richard L. White

Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218,

Robert H. Becker

Physics Dept., University of California, Davis, CA 95616
and IGPP/Lawrence Livermore National Laboratory,

David J. Helfand

Astronomy Dept., Columbia University, New York, NY 10027,

Michael D. Gregg

IGPP/Lawrence Livermore National Laboratory,


We present a catalog of 138,665 radio sources derived from the initial 1550 square degrees of the FIRST survey. The survey parameters are reviewed and a map depicting the coverage for the first two observing sessions is presented. We then describe in detail our algorithm for radio source detection and parameterization, as well as our procedures for constructing the final catalog. The results of extensive tests for astrometric and photometric accuracy, as well as for uncertainties in source extent and morphological characterization are presented. Source positions are all good to better than tex2html_wrap_inline814 , and the flux density scale is accurate to 5%; our elliptical Gaussian fitting procedure is shown both to provide a high-fidelity representation of source morphology for most objects, and to characterize correctly bright sources extended on scales down to tex2html_wrap_inline816 the synthesized beam size of tex2html_wrap_inline818 . We use the catalog to construct a tex2html_wrap_inline820 relation for 20-cm radio sources over four decades of flux density, finding excellent agreement with previous determinations from smaller surveys. As one example of the catalog's utility, we present comparisons with the Guide Star Catalog, the IRAS Faint Source catalog, and the ROSAT WGA catalog, identifying radio counterparts to thousands of the objects. Complete instructions for access to this FIRST catalog and subsequent updates thereto are provided.

Published in The Astrophysical Journal, 475, 479 (1997)
© 1997 The American Astronomical Society

Keywords: catalogs -- galaxies: quasars: general -- infrared: galaxies -- X-rays: galaxies -- radio continuum: galaxies -- radio continuum: stars -- surveys

Richard L. White,
FIRST Home Page
1996 Aug 16