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Related papers: The Quasar-frame Velocity Distribution of Narrow C…

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Using data from the Sloan Digital Sky Survey data release 3 (SDSS DR3) we investigate how narrow (<700km/s) CIV and MgII quasar absorption line systems are distributed around quasars. The CIV absorbers lie in the redshift range 1.6 < z < 4…

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

Using the extremely high S/N quasar absorption-line sample described in the first paper of the series, we investigate which intergalactic CIV absorption line systems could be directly associated with galactic outflows at z = 2 - 3.5 from an…

Astrophysics · Physics 2008-11-26 Antoinette Songaila

We discuss the nature and origin of a rich complex of narrow absorption lines in the quasar J102325.31+514251.0 at redshift 3.447. We measure nine C IV(\lambda1548,1551) absorption line systems with velocities from -1400 to -6200 km/s, and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Leah E. Simon , Fred Hamann

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

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

We present high resolution radio data at 3.5 and 20 cm from the VLA in the A configuration for 144 quasars with known CIV absorption line properties. Using these measurements, we compare and contrast a number of quasar orientation…

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 present the results of a search for variability in the equivalent widths (EWs) of narrow, associated (Delta v < 5,000 km/s) absorption lines found in the UV spectra of z < 1.5 quasars. The goal of this search was to use variability as a…

Astrophysics · Physics 2009-11-10 J. H. Wise , M. Eracleous , J. C. Charlton , . R. Ganguly

We report the first discovery of the emergence of a high-velocity broad-line outflow in a luminous quasar, J105400.40+034801.2 at redshift z ~ 2.1. The outflow is evident in ultraviolet CIV and SiIV absorption lines with velocity shifts v ~…

Astrophysics · Physics 2009-11-13 F. Hamann , K. F. Kaplan , P. Rodriguez Hidalgo , J. X. Prochaska , S. Herbert-Fort

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 assemble 3524 quasars from Sloan Digital Sky Survey (SDSS) with repeated observations to search for variations of narrow C IV1548,1551 and Mg II2796,2803 absorption doublets in spectral regions shortward of 7000 Ang at the observed…

Astrophysics of Galaxies · Physics 2015-09-22 Zhi-Fu Chen , Qiu-Sheng Gu , Yan-Mei Chen , Yue Cao

We investigate the properties of the circumgalactic gas in the halo of quasar host galaxies from CIV absorption line systems. Optical spectroscopy of closely aligned pairs of quasars (projected distance \leq 200 kpc) obtained at the Gran…

Astrophysics of Galaxies · Physics 2016-01-27 M. Landoni , R. Falomo , A. Treves , R. Scarpa , E. P. Farina

(Abridged) With the goal of investigating the nature of OVI absorbers at high redshifts, we study the effects of proximity to the background quasar. In a sample of sixteen quasars at z(QSO) between 2.14 and 2.87 observed at 6.6 km/s…

Astrophysics · Physics 2009-11-13 Andrew J. Fox , Jacqueline Bergeron , Patrick Petitjean

We present the results of a study of QSO Absorption Line Systems (QSOALSs) with respect to intrinsic QSO properties using an updated catalog of data in the literature. We have searched the literature for 6 and 20 cm radio flux densities and…

This work provides evidence that a large fraction of \ion{C}{IV} narrow absorption lines (NALs) seen along the line of sight to distant quasars are due to accretion disk winds, while also seeking to understand the relationship between NALs…

Astrophysics of Galaxies · Physics 2019-08-14 Robert B. Stone , Gordon T. Richards

This paper statistically investigates the properties of C IV and Mg II narrow absorption lines (NALs) to look for velocity cuts that can well constrain quasar-associated NALs. The coverage fraction (f_c) is defined as the ratio between the…

Astrophysics of Galaxies · Physics 2018-01-24 Chen Zhi-Fu , Pan Da-Sheng

We present the detection of a rare case of dramatic strengthening in the UV absorption profiles in the spectrum of the quasar J115122.14+020426.3 between observations ~2.86 years apart in the quasar rest-frame. A 2001 spectrum from the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Paola Rodríguez Hidalgo , Michael Eracleous , Jane Charlton , Fred Hamann , Michael Murphy , Daniel Nestor

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

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
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