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Related papers: Radio Emission from Broad Absorption Line Quasars

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We present the results of an optical photometric monitoring program of 10 extremely radio loud broad absorption line quasars (RL-BALQSOs) with radio-loudness parameter, R, greater than 100 and magnitude g_i < 19. Over an observing run of…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Ravi Joshi , Hum Chand

Broad absorption lines (BALs), seen in a small fraction of both the radio-quiet and radio-loud quasar populations, are probably caused by the outflow of gas with high velocities and are part of the accretion process. The presence of BALs is…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-30 Marcin P. Gawronski , Magdalena Kunert-Bajraszewska

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

XMM-Newton observations of 29 high redshift (z>2) quasars, including seven radio-quiet, 16 radio-loud and six Broad Absorption Line (BAL) objects, are presented; due to the high redshifts, the rest-frame energy bands extend up to \~30-70…

Astrophysics · Physics 2009-11-13 K. L. Page , J. N. Reeves , P. T. O'Brien , M. J. L. Turner

The origin of the radio emission in Radio Quiet (RQ) quasars is not established yet. Important hints can be provided by the spectral slope, and its relation to other emission properties. We compiled the highest resolution 5 and 8.4 GHz VLA…

Astrophysics of Galaxies · Physics 2018-11-28 Ari Laor , Ranieri D. Baldi , Ehud Behar

The origin of radio emission in different populations of radio-quiet quasars is relatively unknown, but recent work has uncovered various drivers of increased radio-detection fraction. In this work, we pull together three known factors:…

We conducted a survey of quasar outflows using the VLT/X-shooter spectrograph. When choosing the 14 BAL and mini-BALs comprising this sample, the data did not cover the S IV and S IV* troughs, whose ratio can be used to determine the…

Astrophysics of Galaxies · Physics 2019-05-14 Xinfeng Xu , Nahum Arav , Timothy Miller , Chris Benn

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

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 present radio and X-ray observations, as well as optical light curves, for a subset of 26 BL Lac candidates from the Sloan Digital Sky Survey (SDSS) lacking strong radio emission and with z<2.2. Half of these 26 objects are shown to be…

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

The origin of the radio emission in radio-quiet quasars (RQQ) is not established yet. We present new VLBA observations at 1.6 and 4.9 GHz of ten RQQ (nine detected), which together with published earlier observations of eight RQQ (five…

Astrophysics of Galaxies · Physics 2023-08-09 Sina Chen , Ari Laor , Ehud Behar , Ranieri D. Baldi , Joseph D. Gelfand

The ultraviolet broad absorption lines have been seen in the spectra of quasars at high redshift, and are generally considered to be caused by outflows with velocities from thousands kilometers per second to one tenth of the speed of light.…

Astrophysics of Galaxies · Physics 2015-11-30 WeiMin Yi , XueBing Wu , FeiGe Wang , JinYi Yang , Qian Yang , JinMing Bai

We use Southern African Large Telescope (SALT) to perform long-slit spectroscopic observations of 23 newly discovered radio-loud quasars (RLQs) at $2.7<z<3.3$. The sample consists of powerful AGN brighter than 200 mJy at 1.4 GHz and is…

A sample of 67 Broad Absorption Line quasars (BALQSOs) from the Large Bright Quasar Survey (LBQS) is used to estimate the observed and intrinsic fraction of BAL quasars in optically--selected samples at intermediate (B_J \simeq 18.5)…

Astrophysics · Physics 2014-10-13 Paul C. Hewett , Craig B. Foltz

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 present the pc-scale radio spectra of a representative sample of 13 Palomar-Green radio-quiet quasars, based on our new Very Long Baseline Array (VLBA) observations at 8.4 and 23.6 GHz and our earlier VLBA studies at 1.5 and 5.0 GHz. The…

Astrophysics of Galaxies · Physics 2024-12-19 Sina Chen , Ari Laor , Ehud Behar , Ranieri D. Baldi , Joseph D. Gelfand , Amy E. Kimball

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 report spectropolarimetry of 30 radio-selected broad absorption line (BAL) quasars with the Keck Observatory, 25 from the sample of Becker et al. (2000). Both high and low-ionization BAL quasars are represented, with redshifts ranging…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 M. A. DiPompeo , M. S. Brotherton , R. H. Becker , H. D. Tran , M. D. Gregg , R. L. White , S. A. Laurent-Muehleisen

Broad Absorption Line Quasars (BAL QSOs) have been found to be associated with extremely compact radio sources. These reduced dimensions can be either due to projection effects or these objects might actually be intrinsically small.…

Cosmology and Nongalactic Astrophysics · Physics 2009-03-31 F. M. Montenegro-Montes , K. -H. Mack , C. R. Benn , R. Carballo , D. Dallacasa , J. I. González-Serrano , J. Holt , F. Jiménez-Luján