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arXiv · astro-ph/9604148

The FIRST Bright QSO Survey

Michael D. Gregg·Robert H. Becker·Richard L. White·David J. Helfand·Richard G. McMahon·Isobel M. Hook
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Abstract

The FIRST Radio Survey provides a new resource for constructing a large quasar sample. With source positions accurate to better than 1\arcsec\ and a point source sensitivity limit of 1 mJy, it reaches 50 times deeper than previous radio catalogs. We report here on the results of the pilot phase for a FIRST Bright Quasar Survey (FBQS). Based on matching the radio catalog from the initial 300 deg$^2$ of FIRST coverage with the optical catalog from the Automated Plate Machine (APM) digitization of Palomar Sky Survey plates, we have defined a sample of 219 quasar candidates brighter than E = 17.50. We have obtained optical spectroscopy for 151 of these and classified 25 others from the literature, yielding 69 quasars or Seyfert~1 galaxies, of which 51 are new identifications. The brightest new quasar has an E magnitude of 14.6 and z = 0.91; four others are brighter than E = 16. The redshifts range from z=0.12 to 3.42. Half of the detected objects are radio quiet with L$_{\rm 21cm} < 10^{32.5}$ ergs/s. We use the results of this pilot survey to establish criteria for the FBQS that will produce a quasar search program which will be 70\% efficient and 95\% complete to a 21-cm flux density limit of 1.0 mJy.

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Michael D. Gregg, Robert H. Becker, Richard L. White, David J. Helfand, Richard G. McMahon, Isobel M. Hook. 1996-04-24. The FIRST Bright QSO Survey. https://doi.org/10.1086/118024

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