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In a spectroscopic follow-up to the VLA FIRST survey, the FIRST Bright Quasar Survey (FBQS) has found 29 radio-selected broad absorption line (BAL) quasars. This sample provides the first opportunity to study the properties of…

We investigate C IV broad absorption line (BAL) variability within a sample of 46 radio-loud quasars (RLQs), selected from SDSS/FIRST data to include both core-dominated (39) and lobe-dominated (7) objects. The sample consists primarily of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 C. A. Welling , B. P. Miller , W. N. Brandt , D. M. Capellupo , R. R. Gibson

We present 13 Broad Absorption Line (BAL) quasars, including 12 new objects, which were identified in the Sloan Digital Sky Survey (SDSS) and matched within 2'' to sources in the FIRST radio survey catalog. The surface density of this…

We present preliminary results from an investigation into broad absorption line (BAL) variability within a sample of 41 radio-loud quasars (RLQs). Using 28 new Hobby-Eberly Telescope (HET) spectra along with earlier Sloan Digital Sky Survey…

High Energy Astrophysical Phenomena · Physics 2012-01-13 B. P. Miller , C. A. Welling , W. N. Brandt , R. R. Gibson

The origin of broad-absorption-line quasars (BAL QSOs) is still an open issue. Accounting for ~20% of the QSO population, these objects present broad absorption lines in their optical spectra generated from outflows with velocities up to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 G. Bruni , K. -H. Mack , E. Salerno , F. M. Montenegro-Montes , R. Carballo , C. R. Benn , J. I. González-Serrano , J. Holt , F. Jiménez-Luján

We report spectropolarimetry of 30 radio-selected broad absorption line (BAL) quasars with the Keck Observatory, 25 from the sample of Becker et al. (2000). Both high and low-ionization BAL quasars are represented, with redshifts ranging…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 M. A. DiPompeo , M. S. Brotherton , R. H. Becker , H. D. Tran , M. D. Gregg , R. L. White , S. A. Laurent-Muehleisen

If broad absorption line (BAL) quasars represent a high covering fraction evolutionary state (even if this is not the sole factor governing the presence of BALs), it is expected that they should show an excess of mid-infrared radiation…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 M. A. DiPompeo , J. C. Runnoe , M. S. Brotherton , A. D. Myers

Broad absorption lines (BALs) are present in the spectra of ~20% of quasars (QSOs); this indicates fast outflows (up to 0.2c) that intercept the observer's line of sight. These QSOs can be distinguished again into radio-loud (RL) BAL QSOs…

We present the multiwavelength spectral energy distributions (SEDs) for 65 luminous broad absorption line (BAL) quasars with redshifts $1.55 \lesssim z \lesssim 3.50$ from the Gemini Near Infrared Spectrograph - Distant Quasar Survey…

Studies of radio-loud (RL) broad absorption line (BAL) quasars indicate that popular orientation-based BAL models fail to account for all observations. Are these results extendable to radio-quiet (RQ) BAL quasars? Comparisons of RL and RQ…

A substantial fraction of quasars display broad absorption lines (BALs) in their rest-frame ultraviolet spectra. While the origin of BALs is thought to be related to the accretion disc wind, it remains unclear whether the observed ratio of…

High Energy Astrophysical Phenomena · Physics 2024-05-22 Takayuki J. Hayashi , Akihiro Doi , Hiroshi Nagai

A new broad absorption line quasar (BAL) sample is derived from the first data released by the Sloan Digital Sky Survey. With 116 objects, it is the largest BAL sample yet assembled. Over the redshift range 1.8 < z < 3.8, the crude fraction…

Astrophysics · Physics 2009-11-07 Alin Tolea , Julian H. Krolik , Zlatan Tsvetanov

We have built a sample of 74 radio-selected broad absorption line quasars from the Sloan Digital Sky Survey Data Release 5 (SDSS DR5) and Faint Images of the Radio Sky at Twenty Centimeters (FIRST), along with a well matched sample of 74…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Michael A. DiPompeo , Michael S. Brotherton , Carlos De Breuck , Sally Laurent-Muehleisen

This work presents the results of a Chandra study of 21 broad absorption line (BAL) radio-loud quasars (RLQs). We conducted a Chandra snapshot survey of 12 bright BAL RLQs selected from SDSS/FIRST data and possessing a wide range of radio…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-24 B. P. Miller , W. N. Brandt , R. R. Gibson , G. P. Garmire , O. Shemmer

Broad absorption line (BAL) quasars are characterized by gas clouds that absorb flux at the wavelength of common quasar spectral features, although blueshifted by velocities that can exceed 0.1c. BAL features are interesting as signatures…

We present multi-frequency observations of a sample of 15 radio-emitting Broad Absorption Line Quasars (BAL QSOs), covering a spectral range between 74 MHz and 43 GHz. They display mostly convex radio spectra which typically peak at about…

Using a sample of $\simeq$144,000 quasars from the Sloan Digital Sky Survey data release 14 we investigate the outflow properties, evident both in absorption and emission, of high-ionization Broad Absorption Line (BAL) and non-BAL quasars…

Astrophysics of Galaxies · Physics 2020-03-19 Amy L. Rankine , Paul C. Hewett , Manda Banerji , Gordon T. Richards

(Abridged). We explore the fraction of radio loud quasars in the eHAQ+GAIA23 sample, which contains quasars from the High A(V) Quasar (HAQ) Survey, the Extended High A(V) Quasar (eHAQ) Survey, and the Gaia quasar survey. All quasars in this…

Astrophysics of Galaxies · Physics 2024-01-08 S. Vejlgaard , J. P. U. Fynbo , K. E. Heintz , J. -K. Krogager , P. Møller , S. J. Geier , L. Christensen , G Ma

We present a new set of 84 Broad absorption line (BAL) quasars ( 1.7 $<$ \zem $<$ 4.4) exhibiting an appearance of \civ BAL troughs over 0.3$-$4.8 rest-frame years by comparing the Sloan Digital Sky Survey Data Release (SDSSDR)-7,…

Astrophysics of Galaxies · Physics 2021-04-07 Sapna Mishra , M. Vivek , Hum Chand , Ravi Joshi

We selected from VLA-FIRST a sample of 94 objects starlike in SDSSS, and with APM colour O-E>2, i.e. consistent with their being high-z QSOs. 78 candidates were classified spectroscopically from published data (mainly SDSS) or observations…

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