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Related papers: Time variability of ultra-fast BAL outflows using …

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In this Letter, we present an analysis of the relation between the variability of broad absorption lines (BALs) and that of the continuum. Our sample is multi-epoch observations of 483 quasars by the Sloan Digital Sky Survey-I/II/III…

Astrophysics of Galaxies · Physics 2017-11-13 Wei-Jian Lu , Ying-Ru Lin , Yi-Ping Qin

FeLoBALs are a rare class of quasar outflows with low-ionization broad absorption lines (BALs), large column densities, and potentially large kinetic energies that might be important for `feedback' to galaxy evolution. In order to probe the…

Astrophysics of Galaxies · Physics 2015-09-09 S. M. McGraw , J. C. Shields , F. W. Hamann , D. M. Capellupo , S. C. Gallagher , W. N. Brandt

We present the variability study of broad absorption lines (BALs) in a uniformly radio-selected sample of 28 BAL quasars using the archival data from the FIRST Bright Quasar Survey (FBQS) and the Sloan Digital Sky Survey (SDSS), as well as…

Astrophysics of Galaxies · Physics 2015-04-17 Shaohua Zhang , Hongyan Zhou , Tinggui Wang , Huiyuan Wang , Xiheng Shi , Bo Liu , Wenjuan Liu , Zhenzhen Li , Shufen Wang

We study the transient (i.e. emerging or disappearing) C IV broad absorption line (BAL) components in 50 radio detected QSOs using multi-epoch spectra available in Sloan Digital Sky Survey DR10. We report the detectionof 6 BALQSOs having at…

Astrophysics of Galaxies · Physics 2015-11-11 M. Vivek , R. Srianand , N. Gupta

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) found in a significant fraction of quasar spectra identify high-velocity outflows that might be present in all quasars and could be a major factor in feedback to galaxy evolution. Understanding the nature of…

The variability of the broad absorption lines is investigated for a broad absorption line (BAL) QSO, SDSS J022844.09+000217.0 (z = 2.719), with 18 SDSS/BOSS spectra covering 4128 days in the observed frame. With the ratio of the rms…

Astrophysics of Galaxies · Physics 2016-10-05 Zhi-Cheng He , Wei-Hao Bian , Xiao-Lei Jiang , Yue-Feng Wang

We present an analysis of the broad absorption line (BAL) velocity shift that appeared in one of the outflow systems in quasar SDSS J1042+1646. Observations were taken by the Hubble Space Telescope/Cosmic Origin Spectrograph in 2011 and…

Astrophysics of Galaxies · Physics 2020-03-25 Xinfeng Xu , Nahum Arav , Timothy Miller , Gerard A. Kriss , Rachel Plesha

We discover that some of the broad absorption lines (BALs) are actually a complex of narrow absorption lines (NALs). As a pilot study of this type of BAL, we show this discovery through a typical example in this paper. Utilizing the…

Astrophysics of Galaxies · Physics 2017-11-27 Wei-Jian Lu , Ying-Ru Lin

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 report the discovery in the Sloan Digital Sky Survey and the SDSS-III Baryon Oscillation Spectroscopic Survey of seventeen broad absorption line (BAL) quasars with high-ionization troughs that include absorption redshifted relative to…

We analyze the long-term (rest-frame 3-30 yr) X-Ray variability of eleven broad absorption line (BAL) quasars, mainly to constrain the variation properties of the X-Ray absorbing shielding gas that is thought to play a critical role in BAL…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Cristian Saez , William N. Brandt , Sarah C. Gallagher , Franz E. Bauer , Gordon P. Garmire

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 consider how the profile and multi-year variability properties of a large sample of C IV Broad Absorption Line (BAL) troughs change when BALs from Si IV and/or Al III are present at corresponding velocities, indicating that the…

We report the first discovery of the emergence of a high-velocity broad-line outflow in a luminous quasar, J105400.40+034801.2 at redshift z ~ 2.1. The outflow is evident in ultraviolet CIV and SiIV absorption lines with velocity shifts v ~…

Astrophysics · Physics 2009-11-13 F. Hamann , K. F. Kaplan , P. Rodriguez Hidalgo , J. X. Prochaska , S. Herbert-Fort

The quasar PDS 456 (at redshift ~0.184) has a prototype ultra-fast outflow (UFO) measured in X-rays. This outflow is highly ionized with relativistic speeds, large total column densities log N_H(cm^-2) > 23, and large kinetic energies that…

Astrophysics of Galaxies · Physics 2018-01-24 Fred Hamann , George Chartas , James Reeves , Emanuele Nardini

Broad Absorption Line (BAL) trough variability is predominantly due to cloud motion transverse to our line of sight. The rate at which the variability occurs indicates the velocity of the cloud, which can provide constraints on the cloud's…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-12 Jesse A. Rogerson , Patrick B. Hall , Chelsea MacLeod , Zeljko Ivezic

We discover the significant (significance level of >99%) correlations between the fractional variation of the ionizing continuum and that of the C IV and/or Si IV BALs in each of 21 BAL quasars that have at least five-epoch observations…

Astrophysics of Galaxies · Physics 2019-09-25 Wei-Jian Lu , Ying-Ru Lin

We compile a large sample of broad absorption lines (BAL) quasars with X-ray observations from the \xmm archive data and Sloan Digital Sky Survey Data Release 5. The sample consists of 41 BAL QSOs. Among 26 BAL quasars detected in X-ray,…

Astrophysics · Physics 2008-12-18 LuLu Fan , HuiYuan Wang , Tinggui Wang , Junxian Wang , Xiaobo Dong , Kai Zhang , Fuzhen Cheng

We present results of our time variability studies of Mg II and Al III absorption lines in a sample of 22 Low Ionization Broad Absorption Line QSOs (LoBAL QSOs) at 0.2 <= zem <= 2.1 using the 2m telescope at IUCAA Girawali Observatory over…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 M. Vivek , R. Srianand , P. Petitjean , V. Mohan , A. Mahabal , S. Samui