English
Related papers

Related papers: Variable X-ray Absorption in mini-BAL QSOs

200 papers

We report on the analysis of a short XMM-Newton observation of the reddened Type 1 QSO 2MASS 234449+1221 first identified in the Two Micron All-Sky Survey. The underlying X-ray continuum is found to be typical of a broad-line active galaxy,…

Astrophysics · Physics 2009-11-13 K. A. Pounds , B. J. Wilkes , K. L. Page

We present a statistical analysis of the variability of broad absorption lines (BALs) in quasars using the large multi-epoch spectroscopic dataset of the Sloan Digital Sky Survey Data Release 12 (SDSS DR12). We divide the sample into two…

Astrophysics of Galaxies · Physics 2017-04-03 Zhicheng He , Tinggui Wang , Hongyan Zhou , Weihao Bian , Guilin Liu , Chenwei Yang , Liming Dou , Luming Sun

We present continued analysis of a sample of low-redshift iron low-ionization broad absorption-line quasars (FeLoBALQs). Choi et al. (2022) presented $SimBAL$ spectral analysis of BAL outflows in 50 objects. Leighly et al. (2022) analyzed…

Quasars selected in optical surveys by means of their blue or UV excess are known to be strong emitters in the X-rays, except for Broad Absorption Line (BAL) objects. In this paper we study the X-ray emission of quasars selected through…

Astrophysics · Physics 2009-11-06 G. Risaliti , A. Marconi , R. Maiolino , M. Salvati , P. Severgnini

We present new more sensitive high-resolution radio observations of a compact broad absorption line (BAL) quasar, 1045+352, made with the EVN+MERLIN at 5 GHz. They allowed us to trace the connection between the arcsecond structure and the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Magdalena Kunert-Bajraszewska , Agnieszka Janiuk , Marcin P. Gawronski , Aneta Siemiginowska

Broad Absorption Line Quasars (BALQs) are actively accreting supermassive black holes that have strong outflows characterized by broad absorption lines in their rest-UV spectra. Variability in these absorption lines occurs over months to…

Background quasars are potentially sensitive probes of galactic outflows provided that one can determine the origin of the absorbing material since both gaseous disks and strong bipolar outflows can contribute to the absorption…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 N. Bouche , W. Hohensee , R. Vargas , G. G. Kacprzak , C. L. Martin , J. Cooke , C. W. Churchill

We analyze the VLT/UVES spectrum of the quasar SDSS J143907.5-010616.7, retrieved from the UVES Spectral Quasar Absorption Database. We identify two outflow systems in the spectrum: a mini broad absorption line (mini-BAL) system and a…

Astrophysics of Galaxies · Physics 2022-08-23 Doyee Byun , Nahum Arav , Andrew Walker

The X-ray weakness of broad absorption line (BAL) quasars in comparison to non-BAL objects is possibly caused by the absorption of X-ray emission by the shielding material near the equatorial plane. On the other hand, the radio-loud BALQSOs…

Astrophysics of Galaxies · Physics 2015-06-23 M. Kunert-Bajraszewska , K. Katarzynski , A. Janiuk

This paper presents new X-ray observations of Mrk 231, an active galaxy of particular interest due to its large infrared luminosity and the presence of several blueshifted broad absorption line (BAL) systems, a phenomenon observed in a…

Astrophysics · Physics 2009-10-30 T. J. Turner

Understanding the links between different phases of outflows from active galactic nuclei is a key goal in extragalactic astrophysics. Here we compare [OIII] $\lambda\lambda$4960,5008 outflow signatures in quasars with and without Broad…

BeppoSAX observed several galactic binary X-ray pulsars during the Science Verification Phase and in the first year of the regular program. The complex emission spectra of these sources are an ideal target for the BeppoSAX instrumentation,…

We present the rest-frame ultraviolet-optical spectral properties of 65 broad absorption line (BAL) quasars from the Gemini Near Infrared Spectrograph-Distant Quasar Survey (GNIRS-DQS). These properties are compared with those of 195…

We observed the quasar PG1211+143 using the Cosmic Origins Spectrograph on the Hubble Space Telescope in April 2015 as part of a joint campaign with the Chandra X-ray Observatory and the Jansky Very Large Array. Our ultraviolet spectra…

High Energy Astrophysical Phenomena · Physics 2019-01-24 Gerard A. Kriss , Julia C. Lee , Ashkbiz Danehkar , Michael A. Nowak , Taotao Fang , Martin J. Hardcastle , Joseph Neilsen , Andrew Young

Aims. We have searched for temporal variations of narrow absorption lines in high resolution quasar spectra. A sample of 5 distant sources have been assembled, for which 2 spectra - VLT/UVES or Keck/HIRES - taken several years apart are…

Astrophysics of Galaxies · Physics 2015-09-23 P. Boissé , J. Bergeron , J. X. Prochaska , C. Péroux , D. G. York

We report on the spectral confirmation of 18 QSO candidates from the "QUasars as BRIght beacons for Cosmology in the Southern hemisphere'' survey (QUBRICS), previously observed in the optical band, for which we acquired new spectroscopic…

We use MUSE adaptive optics (AO) data in Narrow Field Mode to study the properties of the ionised gas in MR 2251-178 and PG 1126-041, two nearby (z~0.06) bright quasars hosting sub-pc scale Ultra Fast Outflows (UFOs) detected in the X-ray…

High velocity (HV) outflows are an important but poorly understood aspect of quasar/SMBH evolution. Outflows during the luminous accretion phase might play a critical role in "unveiling" young dusty AGN and regulating star formation in the…

Astrophysics · Physics 2007-05-23 Paola Rodriguez Hidalgo , Fred Hamann , Daniel Nestor , Joseph Shields

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 present results from three Suzaku observations of the z=3.91 gravitationally lensed broad absorption line quasar APM 08279+5255. We detect strong and broad absorption at rest-frame energies of <2 keV (low-energy) and 7-12 keV…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-15 C. Saez , G. Chartas , W. N. Brandt
‹ Prev 1 8 9 10 Next ›