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Related papers: Broad Absorption Line Variability in Radio-Loud Qu…

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Broad absorption line quasars (BAL QSOs) are objects showing absorption from relativistic outflows, with velocities up to 0.2c. These manifest, in about 15% of quasars, as absorption troughs on the blue side of UV emission lines, such as C…

Astrophysics of Galaxies · Physics 2015-10-07 G. Bruni , K. -H. Mack , F. M. Montenegro-Montes , M. Brienza , J. I. González-Serrano

We select a sample of $\sim 4200$ traditionally defined broad absorption line quasars (BALQs) from the Fifth Data Release quasar catalog of the Sloan Digital Sky Survey. For a statistically homogeneous quasar sample with $1.7\le z\le 4.2$,…

A candidate radio-loud broad absorption line quasar (RLBAL) has been reported by Becker et al. (1997). We present JHK observations of this object and three other radio-detected BALs taken with the new Michigan-Dartmouth-MIT/Ohio…

Astrophysics · Physics 2009-10-30 Patrick B. Hall , Paul Martini , D. L. Depoy , Ian Gatley

Quasar spectra have a variety of absorption lines whose origins range from energetic winds expelled from the central engines to unrelated, intergalactic clouds. We present multi-epoch, medium resolution spectra of eight quasars at z~2 that…

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…

Multi-frequency 1.7, 5 and 8.4-GHz VLBA observations of a radio-loud broad absorption line (BAL) quasar 1045+352 are presented. It is a young compact steep spectrum (CSS) object and its asymmetric, two-sided morphology on a scale of several…

Astrophysics · Physics 2008-11-26 Magdalena Kunert-Bajraszewska , Andrzej Marecki

We have carried out a survey with the Chandra X-ray Observatory of a sample of 10 optically bright broad absorption line (BAL) QSOs. Eight out of ten sources are detected. The 6 brightest X-ray sources have only high ionization BALs…

Astrophysics · Physics 2009-11-06 Paul J. Green , Thomas L. Aldcroft , Smita Mathur , Belinda J. Wilkes , Martin Elvis

We isolate a set of quasars that exhibit emergent C iv broad absorption lines (BALs) in their spectra by comparing spectra in the SDSS Data Release 7 and the SDSS/BOSS Data Releases 9 and 10. After visually defining a set of emergent BALs,…

We have compiled the largest sample of multiwavelength spectral energy distributions (SEDs) of Broad Absorption Line (BAL) quasars to date, from the radio to the X-ray. We present new Spitzer MIPS (24, 70, and 160 micron) observations of 38…

Astrophysics · Physics 2009-06-23 S. C. Gallagher , D. C. Hines , M. Blaylock , R. S. Priddey , W. N. Brandt , E. E. Egami

We performed high resolution radio observations of a new sample of ten BAL quasars using both the VLBA and EVN at 5 GHz. All the selected sources have balnicity indices (BI) more than 0 and radio flux densities less than 80 mJy at 1.4 GHz.…

Astrophysics of Galaxies · Physics 2015-07-15 M. Kunert-Bajraszewska , M. Ceglowski , K. Katarzynski , C. Roskowinski

We have carried out the first systematic survey of the sub-millimeter properties of broad absorption line (BAL) quasars. 30 BAL quasars drawn from a homogeneously selected sample from the Sloan Digital Sky Survey at redshifts 2<z<2.6 were…

Astrophysics · Physics 2009-11-10 Chris J. Willott , Steve Rawlings , Jennifer A. Grimes

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

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 investigated the rest-frame $\approx$0.1-5 year X-ray variability properties of an unbiased and uniformly selected sample of 24 BAL and 35 mini-BAL quasars, making it the largest representative sample used to investigate such…

Astrophysics of Galaxies · Physics 2020-09-30 John Timlin , W. N. Brandt , Shifu Zhu

It is been known for more than a decade that BALQSOs (broad absorption line quasars) are highly attenuated in the X-ray regime compared to other quasars, especially in the soft band ($< $ 1 keV). Using X-ray selection techniques we have…

Astrophysics · Physics 2009-11-13 Kajal K. Ghosh , Brian Punsly

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

We probe the small-scale absorption line variability using absorption depth based analysis of a sample of 64 ultra-fast outflow (UFO) C IV broad absorption line (BAL) quasars monitored using the Southern African Large Telescope. We confirm…

Astrophysics of Galaxies · Physics 2024-01-01 P. Aromal , R. Srianand , P. Petitjean

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…

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 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
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