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The FIRST Bright Quasar Survey III. The South Galactic Cap

Robert H. Becker·Richard L. White·Michael D. Gregg·Sally A. Laurent-Muehleisen·Michael S. Brotherton·Chris D. Impey·Frederic H. Chaffee·Gordon T. Richards·David J. Helfand·Mark Lacy·Frederic Courbin·Deanne D. Proctor
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Abstract

We present the results of an extension of the FIRST Bright Quasar Survey (FBQS) to the South Galactic cap, and to a fainter optical magnitude limit. Radio source counterparts with SERC R magnitudes brighter than 18.9 which meet the other FBQS criteria are included. We supplement this list with a modest number of additional objects to test our completeness for quasars with extended radio morphologies. The survey covers 589 square degrees in two equatorial strips in the southern cap. We have obtained spectra for 86% of the 522 candidates, and find 321 radio-selected quasars of which 264 are reported here for the first time. A comparison of this fainter sample with the FBQS sample shows the two to be generally similar. Fourteen new broad absorption line (BAL) quasars are included in this sample. When combined with the previously identified BAL quasars in our earlier papers, we can discern a break in the frequency of BAL quasars with radio loudness, namely that the relative number of high-ionization BAL quasars drops by a factor of four for quasars with a radio-loudness parameter R* > 100.

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Robert H. Becker, Richard L. White, Michael D. Gregg, Sally A. Laurent-Muehleisen, Michael S. Brotherton, Chris D. Impey, Frederic H. Chaffee, Gordon T. Richards, David J. Helfand, Mark Lacy, Frederic Courbin, Deanne D. Proctor. 2001-04-17. The FIRST Bright Quasar Survey III. The South Galactic Cap. https://doi.org/10.1086/321798

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