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We describe two studies designed to characterize the total column densities, kinetic energies, and acceleration physics of broad absorption line (BAL) outflows in quasars. The first study uses new Chandra X-ray and ground-based rest-frame…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-04 Fred Hamann , Daniel Capellupo , George Chartas , Sean McGraw , Paola Rodriguez Hidalgo , Joseph Shields , Jane Charlton , Michael Eracleous

Photoionization modeling of certain low-ionization broad absorption lines in quasars implies very compact (Delta R~0.01 pc), galaxy-scale (R kpc) absorbers blueshifted by several 1000 km s^-1. While these are likely signatures of quasar…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-09 C. -A. Faucher-Giguere

The winds of ionized gas driven by Active Galactic Nuclei (AGN) can be studied through absorption lines in their X-ray spectra. A recurring feature of these outflows is their broad ionization distribution, including essentially all…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Jonathan Stern , Ehud Behar , Ari Laor , Alexei Baskin , Tomer Holczer

Quasar feedback models often predict an expanding hot gas bubble which drives a galaxy-scale outflow. In many circumstances this hot gas radiates inefficiently and is therefore difficult to observe directly. We present an indirect method to…

Astrophysics of Galaxies · Physics 2016-03-23 Jonathan Stern , Claude-Andre Faucher-Giguere , Nadia L. Zakamska , Joseph F. Hennawi

Spectroscopic observations of quasar outflows at rest-frame 500-1000 Angstrom have immense diagnostic power. We present analyses of such data, where absorption troughs from three important ions are measured: first, O IV and O IV* that allow…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Nahum Arav , Benoit Borguet , Carter Chamberlain , Doug Edmonds , Charles Danforth

We analyze the hydrostatic effect of AGN radiation pressure on optically thick gas in the host galaxy. We show that in luminous AGN, the radiation pressure likely confines the ionized layer of the illuminated gas. Radiation pressure…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-04 Jonathan Stern , Ari Laor , Alexei Baskin

An analysis of ~19500 narrow (<200 km/s) CIV 1548.2,1550.8 absorbers in ~34000 Sloan Digital Sky Survey quasar spectra is presented. The statistics of the number of absorbers as a function of outflow-velocity shows that in approximately…

Astrophysics of Galaxies · Physics 2015-06-22 Rebecca A. A. Bowler , Paul C. Hewett , James T. Allen , Gary J. Ferland

Broad absorption line quasars are among the objects presenting the fastest outflows. The launching mechanism itself is not completely understood. Models in which they could be launched from the accretion disk, and then curved and…

Astrophysics of Galaxies · Physics 2017-07-12 G. Bruni , K. -H. Mack , F. M. Montenegro-Montes , M. Brienza , J. I. González-Serrano

Observational evidence revealing the main mechanisms that accelerate quasar outflows has proven difficult to obtain, due to the complexity of the absorption features that this gas produces in the spectra of the emission sources. We build 36…

Astrophysics of Galaxies · Physics 2019-12-18 Lluís Mas-Ribas , Renate Mauland

We report on the analysis of a ~60 ksec XMM observation of the bright, narrow emission line quasar PG 1211+143. Absorption lines are seen in both EPIC and RGS spectra corresponding to H- and He-like ions of Fe, S, Mg, Ne, O, N and C. The…

Astrophysics · Physics 2010-04-06 K. A. Pounds , J. N. Reeves , A. R. King , K. L. Page , P. T. O'Brien , M. J. L. Turner

Quasar outflows carry mass, momentum and energy into the surrounding environment, and have long been considered a potential key factor in regulating the growth of supermassive black holes and the evolution of their host galaxies. A crucial…

We report the detection of OVI 1031,1037 and NV 1238,1242 absorption in a system of "mini-broad" absorption lines (mini-BALs) previously reported to have variable CIV 1548,1550 in the quasar PG0935+417. The formation of these lines in an…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Paola Rodríguez Hidalgo , Fred Hamann , Patrick Hall

We present HST/COS observations of highly ionized absorption lines associated with a radio-loud QSO at $z=1.1319$. The absorption system has multiple velocity components, tracing gas that is largely outflowing from the QSO at velocities of…

We report on quasar outflow properties revealed by analyzing more than 60 composite outflow spectra built from $\sim 60\,000$ CIV absorption troughs in the SDSS-III/BOSS DR12QBAL catalog. We assess the dependences of the equivalent widths…

Astrophysics of Galaxies · Physics 2020-01-08 Lluís Mas-Ribas

Narrow absorption line (NAL) outflows are an important yet poorly understood part of the quasar outflow phenomenon. We discuss one particular NAL outflow that has high speeds, time variability, and moderate ionizations like typical BAL…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-18 Fred Hamann , Leah Simon , Paola Rodriguez Hidalgo , Daniel Capellupo

We report on a variable high-velocity narrow absorption line outflow in the redshift 2.3 quasar J2123-0050. Five distinct outflow systems are detected with velocity shifts from -9710 to -14,050 km/s and CIV 1548,1551 line widths of FWHM =…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 F. Hamann , N. Kanekar , J. X. Prochaska , M. T. Murphy , S. Ellison , A. L. Malec , N. Milutinovic , W. Ubachs

Following the discovery of X-ray absorption in a high velocity outflow from the bright quasar PG1211+143 we have searched for similar features in XMM archival data of a second (high accretion rate) quasar PG0844+349. Evidence is found for…

Astrophysics · Physics 2009-11-07 K. A. Pounds , A. R. King , K. L. Page , P. T. O'Brien

We present new results from our study of the X-rayed outflow of the z = 3.91 gravitationally lensed broad absorption line (BAL) quasar APM 08279+5255. These results are based on spectral fits to all the long exposure observations of APM…

High Energy Astrophysical Phenomena · Physics 2015-05-28 C. Saez , G. Chartas

We present absorption line analysis of the outflow in the quasar IRAS F04250-5718. Far-ultraviolet data from the Cosmic Origins Spectrograph onboard the Hubble Space Telescope reveal intrinsic narrow absorption lines from high ionization…

Quasar accretion disk winds observed via broad absorption lines (BALs) in the UV produce strong continuous absorption in X-rays. The X-ray absorber is believed to serve critically as a radiative shield to enable radiative driving. However,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Fred Hamann , George Chartas , Sean McGraw , Paola Rodriguez Hidalgo , Joseph Shields , Daniel Capellupo , Jane Charlton , Michael Eracleous
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