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1 Introduction

Radio-loud quasars and broad absorption line (BAL) quasars (QSOs) each constitute tex2html_wrap_inline18910% of the total quasar population (Foltz et al. 1990; Weymann et al. 1991) but have always appeared to be mutually exclusive classes (Stocke et al. 1992). There is little agreement about what determines quasar radio luminosities or what the relationship is between broad absorption lines and radio power. The BAL QSOs can be further subdivided into high and low-ionization objects (Hi-BALs and Lo-BALs). The Lo-BALs make up only 10% of the total BAL QSO population (Weymann et al. 1991) and are usually recognized by the presence of broad absorption from Si II, Mg II, and Al III. In the Lo-BAL population, there has for a decade been only one object, 0059-2735, which also shows narrow absorption lines from metastable excited states of Fe II and Fe III (Hazard et al. 1987). We report here the discovery of two more ``iron Lo-BALs''.

We have undertaken two programs to identify candidate quasars drawn from the NRAOgif Very Large Array (VLA) FIRSTgif Survey (Becker, White, & Helfand 1995; White et al. 1997). Both programs select optical samples for spectroscopy by matching FIRST radio sources to stellar counterparts within 1tex2html_wrap_inline1912 from the APM POSS I catalog (McMahon & Irwin 1992). The FIRST Bright Quasar Survey (FBQS, Gregg et al. 1996) is developing a new, complete sample of radio-selected quasars brighter than 17.5 magnitude on the E plates and with O - E < 2.0gif. The second program is searching specifically for high redshift quasars among very red optical counterparts with O-E > 1.0 with the additional constraint that the sources also have flat radio spectra between 6 and 20 cm (Hook et al. 1996). The FIRST Survey quasar search programs are unique in that they go to much fainter radio levels than previous radio-selected QSO surveys: the 1 mJy flux limit picks up radio-quiet objects out to z tex2html_wrap_inline199 2. Roughly half of the objects in the FBQS pilot sample are, in fact, radio-quiet (Gregg et al. 1996).

For the past two years we have been taking 5Å resolution spectra of these quasar candidates using the Lick 3m Shane telescope, the Kitt Peak National Observatorygif 2.1m and 4m telescopes, and the La Palma 2.5m Isaac Newton telescope. To date, 136 new quasars with R tex2html_wrap_inline203 17.5 have been found in the FBQS and tex2html_wrap_inline189 30 additional quasars have been found in the high redshift program.

Among the new QSOs in the FIRST Survey samples, there are 4 BAL QSOs. Two are of the common Hi-BAL variety, but the other two, one from each program, have very unusual spectra, placing them in the iron Lo-BAL class with the heretofor unique object 0059-2735 (Hazard et al. 1987). Additionally, one of these two is the first known radio-loud BAL QSO.


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Next: 2 Observed Properties of Up: The FIRST Radio-Loud Broad Previous: The FIRST Radio-Loud Broad

Richard L. White, rlw@stsci.edu
FIRST Home Page
1997 Feb 10