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Related papers: Monitoring Quasar Colour Variability in Stripe 82

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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

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

We present absorption variability results for 134 bona fide \mgii\ broad absorption line (BAL) quasars at 0.46~$\lesssim z \lesssim$~2.3 covering days to $\sim$ 10 yr in the rest frame. We use multiple-epoch spectra from the Sloan Digital…

Astrophysics of Galaxies · Physics 2019-06-26 Weimin. Yi , W. N. Brandt , P. B. Hall , M. Vivek , C. J. Grier , N. Filiz Ak , D. P. Schneider , S. M. McGraw

We present a time-variability analysis of 29 broad absorption line quasars (BALQSOs) observed in two epochs by the Sloan Digital Sky Survey (SDSS). These spectra are selected from a larger sample of BALQSOs with multiple observations by…

We present a detailed investigation of the variability of 428 C IV and 235 Si IV Broad Absorption Line (BAL) troughs identified in multi-epoch observations of 291 quasars by the Sloan Digital Sky Survey-I/II/III. These observations…

Broad absorption line (BAL) quasars have been studied for over thirty years. Yet it is still unclear why and when we observe broad absorption lines in quasars. Is this phenomenon caused by geometry or is it connected with the evolution…

Astrophysics of Galaxies · Physics 2014-06-19 Maciej Ceglowski , Magdalena Kunert-Bajraszewska , Bogna Pazderska , Marcin Gawronski

Broad absorption lines (BALs) in quasar spectra identify high velocity outflows that likely exist in all quasars and could play a major role in feedback to galaxy evolution. The variability of BALs can help us understand the structure,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Daniel M. Capellupo , Fred Hamann , Joseph C. Shields , Paola Rodríguez Hidalgo , Tom A. Barlow

The variability of broad absorption lines is investigated for a sample of 188 broad-absorption-line (BAL) quasars (QSOs) ($z > 1.7$) with at least two-epoch observations from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7), covering…

Astrophysics of Galaxies · Physics 2015-11-04 Zhi-Cheng He , Wei-Hao Bian , Xiao-Lei Jiang , Xue Ge

We present an analysis of the variability of broad absorption lines (BALs) in a quasar SDSS J141955.26+522741.1 at $z=2.145$ with 72 observations from the Sloan Digital Sky Survey Data Release 16 (SDSS DR16). The strong correlation between…

Astrophysics of Galaxies · Physics 2021-01-12 Qinyuan Zhao , Zhicheng He , Guilin Liu , Tinggui Wang , Hengxiao Guo , Lu Shen , Guobin Mou

We present a statistical analysis of the variability of broad absorption lines (BALs) in quasars using the large multi-epoch spectroscopic dataset of the Sloan Digital Sky Survey Data Release 12 (SDSS DR12). We divide the sample into two…

Astrophysics of Galaxies · Physics 2017-04-03 Zhicheng He , Tinggui Wang , Hongyan Zhou , Weihao Bian , Guilin Liu , Chenwei Yang , Liming Dou , Luming Sun

Broad absorption lines (BALs) in quasar spectra identify high velocity outflows that likely exist in all quasars and could play a major role in feedback to galaxy evolution. Studying the variability in these BALs can help us understand the…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-30 Daniel M. Capellupo , Fred Hamann , Joseph C. Shields , Jules Halpern , Paola Rodríguez Hidalgo , Tom A. Barlow

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

Broad absorption lines (BALs) in quasar spectra indicate high-velocity outflows that may be present in all quasars and could be an important contributor to feedback to their host galaxies. Variability studies of BALs help illuminate the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Daniel M. Capellupo , Fred Hamann , Joseph C. Shields , Paola Rodríguez Hidalgo , Tom A. Barlow

We investigate the connection between the intrinsic C IV absorption line variability and the continuum flux changes of broad absorption line (BAL) quasars using a sample of 78 sources in the Stripe 82 region. The absorption trough…

Astrophysics of Galaxies · Physics 2019-04-10 M. Vivek

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

We systematically investigate short-timescale ($<$10-day rest-frame) CIV broad absorption-line (BAL) variability to constrain quasar-wind properties and provide insights into BAL-variability mechanisms in quasars. We employ data taken by…

We present results from the largest systematic investigation of broad absorption line (BAL) acceleration to date. We use spectra of 140 quasars from three Sloan Digital Sky Survey programs to search for global velocity offsets in BALs over…

We investigate the correlation between rest-frame UV flux variability of broad absorption line (BAL) quasars and their variability in BAL equivalent widths (EWs) in a various timescale from $<10$~days to a few years in the quasar…

Astrophysics of Galaxies · Physics 2022-10-05 Takashi Horiuchi , Tomoki Morokuma , Toru Misawa , Hidekazu Hanayama , Toshihiro Kawaguchi

Quasar outflows have long been recognized as potential contributors to the co-evolution between supermassive black holes (SMBHs) and their host galaxies. The role of outflows in AGN feedback processes can be better understood by placing…

Astrophysics of Galaxies · Physics 2018-01-31 S. M. McGraw , J. C. Shields , F. W. Hamann , D. M. Capellupo , H. Herbst

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
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