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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 present the analysis of one of the most extreme quasar outflows found to date in our survey of extremely high velocity outflows (EHVO). J164653.72+243942.2 (z ~ 3.04) shows variable CIV1548,1551 absorption at speeds larger than 0.1c,…

We have identified a broad absorption line (BAL) outflow in the HST/STIS spectrum of the quasar QSO B0254-3327B at velocity $v=-3200\text{ km s$^{-1}$}$. The outflow has absorption troughs from ions such as Ne VIII, Na IX, Si XII, and Ne V.…

Astrophysics of Galaxies · Physics 2024-02-22 Doyee Byun , Nahum Arav , Maryam Dehghanian , Gwen Walker , Gerard A. Kriss

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

Quasar outflows are fundamental components of quasar environments that might play an important role in feedback to galaxy evolution. We report on the emergence of a remarkable new outflow absorption-line system in the quasar PG1411+442…

Astrophysics of Galaxies · Physics 2019-06-19 Fred Hamann , Todd M. Tripp , David Rupke , Sylvain Veilleux

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

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

The quasar PDS 456 (at redshift ~0.184) has a prototype ultra-fast outflow (UFO) measured in X-rays. This outflow is highly ionized with relativistic speeds, large total column densities log N_H(cm^-2) > 23, and large kinetic energies that…

Astrophysics of Galaxies · Physics 2018-01-24 Fred Hamann , George Chartas , James Reeves , Emanuele Nardini

Broad absorption lines (BALs) found in a significant fraction of quasar spectra identify high-velocity outflows that might be present in all quasars and could be a major factor in feedback to galaxy evolution. Understanding the nature of…

We present a catalog of high-velocity CIV $\lambda$ 1548,1551 mini-Broad Absorption Lines (mini-BALs) in the archives of the VLT-UVES and Keck-HIRES spectrographs. We identify high-velocity CIV mini-BALs based on smooth rounded BAL-like…

Astrophysics of Galaxies · Physics 2021-02-03 Chen Chen , Fred Hamann , Bo Ma , Michael Murphy

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 accretion-disk outflows might play an important role in galaxy evolution, but they are notoriously difficult to study due to line saturation and blending problems in the Ly-alpha forest. We circumvent these problems by constructing…

Astrophysics of Galaxies · Physics 2018-11-07 Fred Hamann , Hanna Herbst , Isabelle Paris , Daniel Capellupo

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…

We report on the variability of a multi-component broad absorption line (BAL) system observed in the hyper-luminous quasar J1538+0855 at z=3.6. Observations from SDSS, VLT, LBT and Subaru telescopes taken at five different epochs, spanning…

Broad absorption lines (BALs) in quasar spectra indicate high-velocity outflows that may be present in all quasars and could be an important contributor to feedback to their host galaxies. Variability studies of BALs help illuminate the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Daniel M. Capellupo , Fred Hamann , Joseph C. Shields , Paola Rodríguez Hidalgo , Tom A. Barlow

With a 1999 ASCA observation, PG2112+059 became notable as the first Broad Absorption Line (BAL) quasar found to exhibit a typical radio-quiet quasar X-ray continuum underlying a large amount of intrinsic absorption. We present a recent…

Astrophysics · Physics 2009-11-10 S. C. Gallagher , W. N. Brandt , Beverley J. Wills , J. C. Charlton , G. Chartas , A. Laor

We report the discovery of disappearance of Mg ii, Al iii, C iv, and Si iv broad absorption lines (BALs) at the same velocity, accompanied by a new Civ BAL emerging at a higher velocity, in the quasar J0827+4252 at z = 2.038. This is the…

Astrophysics of Galaxies · Physics 2019-01-23 Weimin Yi , M. Vivek , W. N. Brandt , T. Wang , J. Timlin , N. Filiz Ak , D. P. Schneider , J. P. U. Fynbo , Q. Ni , F. Vito , B. L. Indahl , Sameer

We determine the physical conditions and location of the outflow material seen in the mini-BAL quasar SDSS J1111+1437 (z = 2.138). These results are based on the analysis of a high S/N, medium-resolution VLT/X- shooter spectrum. The main…

Astrophysics of Galaxies · Physics 2019-05-13 Xinfeng Xu , Nahum Arav , Timothy Miller , Chris Benn

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
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