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Related papers: Radio Emission from Broad Absorption Line Quasars

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We present a study of a sample of 223 radio-loud quasars (up to redshift $<$0.3) in order to investigate their spectral properties. Twenty-six of these radio-loud quasars are identified as Flat Spectrum Radio Quasars (FSRQs) and fifty-four…

High Energy Astrophysical Phenomena · Physics 2019-10-23 Haritma Gaur , Minfeng Gu , S. Ramya , Hengxiao Guo

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…

A new generation of sensitive X-ray measurements are indicating that the existence of X-ray attenuation column densities, $N_{H}>10^{24}\mathrm{cm}^{-2}$ is quite common amongst broad absorption line quasars (BALQSOs). This is significant…

Astrophysics · Physics 2007-05-23 Brian Punsly , Sebastian Lipari

Most X-ray studies of BALQSOs found significant (N_H~10^{22-24} cm^{-2}) intrinsic column densities of gas absorbing an underlying typical power-law continuum emission, in agreement with expectations from radiatively driven accretion disk…

Astrophysics · Physics 2009-11-13 Margherita Giustini , Massimo Cappi , Cristian Vignali

Radio monitoring of the broad absorption line quasar (BALQSO) Mrk 231 from 13.9 GHz to 17.6 GHz detected a strong flat spectrum flare. Even though BALQSOs are typically weak radio sources, the 17.6 GHz flux density doubled in ~150 days,…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Cormac Reynolds , Brian Punsly , Christopher O'Dea , Natasha Hurley-Walker , Joan Wrobel

This paper presents new optical and near-UV spectra of 11 extremely powerful jetted quasars, with radio to optical flux density ratio $>$ 10$^3$, that concomitantly cover the low-ionization emission of \mgii\ and \hb\ as well as the \feii\…

The origin of the radio emission in radio-quiet quasars (RQQs) has been a matter of debate for a long time. It is not well understood whether the emission is caused by star formation in the host galaxy or by black hole activity of the…

Astrophysics of Galaxies · Physics 2016-04-06 Noelia Herrera Ruiz , Enno Middelberg , Ray P. Norris , Alessandro Maini

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 construct the first X-ray selected sample of radio-loud quasars from the EMSS survey. The X-ray selection allows us to explore the properties of radio-loud quasars 10-100 weaker than classical samples in the radio band. There are no…

Astrophysics · Physics 2007-05-23 Anna Wolter , Annalisa Celotti

We have investigated a sample of 2099 broad absorption line (BAL) quasars with z=1.7-2.2 built from the Sloan Digital Sky Survey Data Release Seven and the Wide-field Infrared Survey. This sample is collected from two BAL quasar samples in…

Astrophysics of Galaxies · Physics 2014-12-24 Shaohua Zhang , Huiyuan Wang , Tinggui Wang , Feijun Xing , Kai Zhang , Hongyan Zhou , Peng Jiang

We present Chandra observations of nine high-redshift quasars (z=2.7-5.9) discovered by the Sloan Digital Sky Survey with weak or undetectable high-ionization emission lines in their UV spectra (WLQs). Adding archival X-ray observations of…

Broad absorption line (BAL) outflows are commonly detected in active galactic nuclei (AGN), but their driving mechanism remains poorly constrained. Here we investigate whether radiation pressure on dust can adequately explain the BAL…

Astrophysics of Galaxies · Physics 2024-09-09 W. Ishibashi , A. C. Fabian , P. C. Hewett

We present new results on X-ray properties of radio loud broad absorption line (BAL) quasars and focus on broad-band spectral properties of a high ionization BAL (HiBAL) compact steep spectrum (CSS) radio-loud quasar 1045+352. This HiBAL…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 M. Kunert-Bajraszewska , A. Siemiginowska , K. Katarzynski , A. Janiuk

We present the method and first results of a survey for high-redshift (z>3) radio-loud quasars, which is based on optical identifications of 2902 flat-spectrum radio sources with S(5GHz)>= 25mJy. The radio sample was defined over a 1600 sq…

Astrophysics · Physics 2009-10-30 I. M. Hook , R. H. Becker , R. G. McMahon , R. L. White

We study the correlations between the Very Long Baseline Array radio emission at 15 GHz, extended emission at 151 MHz, and optical nuclear emission at 5100 AA for a complete sample of 135 compact jets. We use the partial Kendall's tau…

Astrophysics of Galaxies · Physics 2015-03-13 T. G. Arshakian , J. Torrealba , V. H. Chavushyan , E. Ros , M. L. Lister , I. Cruz-González , J. A. Zensus

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

We present Karl G. Jansky Very Large Array (VLA) S- (2--4 GHz), C- (4--8 GHz), and X-band (8--12 GHz) continuum observations toward seven radio-loud quasars at $z>5$. This sample has previously been found to exhibit spectral peaks at…

We present the results from 685 MHz observations with the upgraded Giant Metrewave Radio Telescope (uGMRT) of 22 quasars belonging to the Palomar-Green (PG) quasar sample. Only four sources reveal extended radio structures on $\sim$10-30…

Astrophysics of Galaxies · Physics 2020-12-22 Silpa S. , P. Kharb , L. C. Ho , C. H. Ishwara-Chandra , M. E. Jarvis , C. Harrison

This paper reports very-long-baseline interferometry observations of the radio-loud broad absorption line (BAL) quasar J1020+4320 at 1.7, 2.3, 6.7, and 8.4 GHz using the Japanese VLBI network (JVN) and European VLBI network (EVN). The radio…

While there are a lot of investigations on the optical variability of flat-spectrum radio quasars (FSRQs), not much work has been done on the optical variability of steep-spectrum radio quasars (SSRQs). We investigate the optical…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Minfeng Gu , Y. L. Ai
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