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Broad absorption line (BAL) features in quasar spectra reveal an unambiguous signature of energetic outflows from central supermassive black holes, and thus BAL quasars are prime targets for investigating the potential process of luminous…

Astrophysics of Galaxies · Physics 2020-03-04 Hyunseop Choi , Karen M. Leighly , Donald M. Terndrup , Sarah C. Gallagher , Gordon T. Richards

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

We have discovered two low-ionization broad absorption line quasars in programs to obtain optical spectra for radio-selected quasar candidates from the VLA FIRST Survey (Becker, White, & Helfand 1995). Both belong to the extremely rare…

We conducted the first multi-frequency polarimetric imaging of four broad absorption line (BAL) quasars using Very Long Baseline Array at milli-arcsecond resolutions to investigate the inclination of the non-thermal jet and test the…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Takayuki J. Hayashi , Akihiro Doi , Hiroshi Nagai

Broad absorption line (BAL) quasars probe the high velocity gas ejected by luminous accreting black holes. BAL variability timescales place constraints on the size, location, and dynamics of the emitting and absorbing gas near the…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-16 Daryl Haggard , Kenza S. Arraki , Paul J. Green , Tom Aldcroft , Scott F. Anderson

Broad absorption lines (BALs) in quasar spectra identify high velocity outflows that might exist in all quasars and could play a major role in feedback to galaxy evolution. The viability of BAL outflows as a feedback mechanism depends on…

Astrophysics of Galaxies · Physics 2015-06-22 Daniel M. Capellupo , Fred Hamann , Tom A. Barlow

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…

Roughly 10% of all quasars exhibit Broad Absorption Line (BAL) features which appear to arise in material outflowing at high velocity from the active galactic nucleus (AGN). The details of this outflow are, however, very poorly constrained…

Astrophysics · Physics 2009-10-31 Kunegunda E. Belle , Geraint F. Lewis

We present the results of EVN+MERLIN VLBI polarization observations of 8 Broad Absorption Line (BAL) quasars at 1.6 GHz, including 4 LoBALs and 4 HiBALs with either steep or flat spectra on VLA scales. Only one steep-spectrum source,…

Astrophysics · Physics 2009-11-13 Y. Liu , D. R. Jiang , T. G. Wang , F. G. Xie

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

Broad absorption lines (BALs) in quasar spectra are prominent signatures of high-velocity outflows, which might be present in all quasars and could be a major contributor to feedback to galaxy evolution. Studying the variability in these…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Daniel M. Capellupo , Fred Hamann , Joseph C. Shields , Jules P. Halpern , Tom A. Barlow

The incidence of broad absorption lines (BALs) in quasar samples is often interpreted in the context of a geometric unification model consisting of an accretion disc and an associated outflow. We use the the Sloan Digital Sky Survey (SDSS)…

Astrophysics of Galaxies · Physics 2017-02-08 James H. Matthews , Christian Knigge , Knox S. Long

We report the discovery of a Broad Absorption Line (BAL) of \sim 10^4 km s-1 in width in the previously known BL Lac object PKS 0138-097, which we tentatively identified as a Mg II BAL. This is the first detection of a BAL, which is…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-24 Zhang Shaohua , Wang Huiyuan , Zhou Hongyan , Wang Tinggui , Jiang Peng

We analyze VLT/X-shooter data for 7 quasars, where we study the relationships between their broad absorption line (BAL) and emission line outflows. We find: 1) the luminosity of the [OIII] $\lambda$5007 emission profile decreases with…

Astrophysics of Galaxies · Physics 2020-05-13 Xinfeng Xu , Nadia Zakamska , Nahum Arav , Timothy Miller , Chris Benn

We report the discovery of X-ray broad absorption lines (BALs) from the BALQSO APM 08279+5255 originating from material moving at relativistic velocities with respect to the central source. The large flux magnification by a factor of ~ 100…

Astrophysics · Physics 2009-11-07 G. Chartas , W. N. Brandt , S. C. Gallagher , G. P. Garmire

We report the discovery of five broad-absorption-line (BAL) QSOs in a complete sample of 111 ultraviolet excess (UVX) QSO candidates also detected in the NRAO VLA Sky Survey. All five BAL QSOs, which include two high-ionization BAL QSOs and…

This paper reports very-long-baseline interferometry observations of the radio-loud broad absorption line (BAL) quasar J1020+4320 at 1.7, 2.3, 6.7, and 8.4 GHz using the Japanese VLBI network (JVN) and European VLBI network (EVN). The radio…

We describe two studies designed to characterize the total column densities, kinetic energies, and acceleration physics of broad absorption line (BAL) outflows in quasars. The first study uses new Chandra X-ray and ground-based rest-frame…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-04 Fred Hamann , Daniel Capellupo , George Chartas , Sean McGraw , Paola Rodriguez Hidalgo , Joseph Shields , Jane Charlton , Michael Eracleous

We present an observational study of wind acceleration based on four low-ionization broad absorption line (LoBAL) quasars (J0136, J1238, J1259, J1344). J0136 and J1344 (group-1) are radio quiet and show large BAL-velocity shifts as opposed…

Astrophysics of Galaxies · Physics 2024-02-19 Weimin Yi , P. B. Hall , Zunlin Yuan , W. N. Brandt , D. P. Schneider , Zhicheng He , Jin-Ming Bai , Xue-Bing Wu

We present a catalog of 5039 broad absorption line (BAL) quasars (QSOs) in the Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) QSO catalog that have absorption troughs covering a continuous velocity range >= 2000 km/s. We have fit…