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Related papers: Classification of Broad Absorption Line Quasars wi…

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Broad absorption line (BAL) quasars serve as critical probes for understanding active galactic nucleus (AGN) outflows, black hole accretion, and cosmic evolution. To address the limitations of manual classification in large-scale…

Astrophysics of Galaxies · Physics 2025-11-04 Yangyang Li , Zhijian Luo , Shaohua Zhang , Du Wang , Jianzhen Chen , Zhu Chen , Hubing Xiao , Chenggang Shu

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…

We apply a recently developed method for classifying broad absorption line quasars (BALQSOs) to the latest QSO catalogue constructed from Data Release 5 of the Sloan Digital Sky Survey. Our new hybrid classification scheme combines the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 S. Scaringi , C. E. Cottis , C. Knigge , M. R. Goad

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

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 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…

Broad Absorption Line Quasars (BALQSOs) displaying distinct blue-shifted broad absorption lines. These serve as invaluable probes for unraveling the intricate structure and evolution of quasars, shedding light on the profound influence…

Astrophysics of Galaxies · Physics 2024-06-04 Wei-Bo Kao , Yanxia Zhang , Xue-Bing Wu

Accurate quasar classifications and redshift measurements are increasingly important to precision cosmology experiments. Broad absorption line (BAL) features are present in 15-20\% of all quasars, and these features can introduce systematic…

In this study, we investigated the orientation model of Broad Absorption Line (BAL) quasars using a sample of sources that are common in Sloan Digital Sky Survey (SDSS) Data Release (DR)-16 quasar catalog and Very Large Array (VLA)-Faint…

Astrophysics of Galaxies · Physics 2022-02-02 Akhil Nair , M. Vivek

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 present a catalog of 224 broad absorption line quasars (BALQSOs) from the Sloan Digital Sky Survey's Early Data Release Quasar Catalog, including a relatively complete and homogeneous subsample of 131 BALQSOs. Since the identification of…

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

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

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

The Sloan Digital Sky Survey has confirmed the existence of populations of broad absorption line (BAL) quasars with various unusual properties. We present and discuss twenty-three such objects and consider the implications of their wide…

Correlations in and with the flux transmission of the Lyman$-\alpha$ (Ly$\alpha$) forest in the spectra of high-redshift quasars are powerful cosmological tools, yet these measurements can be compromised if the intrinsic quasar continuum is…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-07 Lauren Ennesser , Paul Martini , Andreu Font-Ribera , Ignasi Pérez-Ràfols

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 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

Broad absorption line (BAL) quasars are often considered X-ray weak relative to their optical/UV luminosity, whether intrinsically (i.e., the coronal emission is fainter) or due to large column densities of absorbing material. The SDSS-V is…

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…

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