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Related papers: Measuring Column Densities in Quasar Outflows: VLT…

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Using high resolution VLT spectra, we study the multi-component outflow systems of two quasars exhibiting intrinsic Fe II absorption (QSO 2359-1241 and SDSS J0318-0600). From the extracted ionic column densities and using photoionization…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 M. A. Bautista , J. P. Dunn , N. Arav , K. T. Korista , M. Moe , C. Benn

We analyze the physical conditions of the outflow seen in QSO 2359-1241 (NVSS J235953-124148), based on high resolution spectroscopic VLT observations. This object was previously studied using Keck/HIRES data. The main improvement over the…

Astrophysics · Physics 2009-11-13 Kirk Korista , Manuel Bautista , Nahum Arav , Maxwell Moe , Elisa Costantini , Chris Benn

With the advent of Chandra and XMM, X-ray lines spectroscopy of AGN outflows is off to an exciting start. In this paper we illuminate some of the complications involved in extracting the outflow's physical conditions (ionization…

Astrophysics · Physics 2007-05-23 Nahum Arav

We re-analyze the HST high resolution spectroscopic data of the intrinsic absorber in NGC 5548 and find that the C IV absorption column density is at least four times larger than previously determined. This increase arises from accounting…

Astrophysics · Physics 2009-11-06 Nahum Arav , Martijn de Kool , Kirk T. Korista

It has been known for 20 years that the absorbing gas in broad absorption line quasars does not completely cover the continuum emission region, and that partial covering must be accounted for to accurately measure the column density of the…

Several studies have shown that the column densities inferred from broad absorption lines (BALs) require extremely high metallicities and phosphorus overabundances -- apparently in conflict with other abundance diagnostics. Here I use HST…

Astrophysics · Physics 2007-05-23 F. Hamann

Spectra of the z_em = 3.268 quasar PKS 2126-158 have been obtained in the range lambda lambda 4300-6620 A with a resolution R = 27000 and an average signal-to-noise ratio s/n = 25 per resolution element. The list of the identified…

Astrophysics · Physics 2011-05-23 V. D'Odorico , S. Cristiani , S. D'Odorico , A. Fontana , E. Giallongo

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 present a detailed analysis of the Astrophysical Research Consortium 3.5 m telescope spectrum of QSO SDSS J0838+2955. The object shows three broad absorption line (BAL) systems at 22,000, 13,000, and 4900 km s^-1 blueshifted from the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Maxwell Moe , Nahum Arav , Manuel A. Bautista , Kirk T. Korista

We analyze new HST/COS spectra for two quasar absorption outflows seen in the quasi-stellar object LBQS 1206+1052. These data cover, for the first time, absorption troughs from $S_{IV}$, $Si_{II}$, and $P_V$. From the ratio of the $S_{IV}$*…

Astrophysics of Galaxies · Physics 2018-10-10 Timothy R. Miller , Nahum Arav , Xinfeng Xu , Gerard A. Kriss , Rachel J. Plesha , Chris Benn , Guilin Liu

We compare X-ray and UV spectroscopic observations of NGC 5548. Both data sets show O VI absorption troughs associated with the AGN outflow from this galaxy. We find that the robust lower limit on the column density of the O VI X-ray trough…

We present high spectral resolution VLT observations of the BAL quasar SDSS J0318-0600. This high quality data set allows us to extract accurate ionic column densities and determine an electron number density of n_e=10^3.3 +/- 0.2 cm^-3 for…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Jay P. Dunn , Manuel A. Bautista , Nahum Arav , Maxwell Moe , Kirk T. Korista , Elisa Costantini , Chris Benn , Sara Ellison , Doug Edmonds

We investigate the applicability of inhomogeneous absorber models in the formation of AGN outflow absorption-troughs. The models we explore are limited to monotonic gradients of absorbing column densities in front of a finite emission…

Astrophysics · Physics 2009-11-10 Nahum Arav , Jelle Kaastra , Gerard A. Kriss , Kirk T. Korista , Jack Gabel , Daniel Proga

In this article, the hydrogen column densities derived from X-ray observations of type II (hidden) quasars and broad absorption line quasars (BALQSOs) are compared. These column densities represent the amount of absorbing material between…

Astrophysics · Physics 2011-02-11 Brian Punsly

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

Context. Quasar outflows are often analyzed to determine their ability to contribute to active galactic nucleus (AGN) feedback. We identified a broad absorption line (BAL) outflow in the VLT/UVES spectrum of the quasar SDSS J1321-0041. The…

Astrophysics of Galaxies · Physics 2024-02-21 Doyee Byun , Nahum Arav , Mayank Sharma , Maryam Dehghanian , Gwen Walker

We analyze absorption troughs from two outflows within PKS J0352-0711 (S1 at $-$1950 km s$^{-1}$ and S2 at $-$3150 km s$^{-1}$) from spectra taken with Hubble Space Telescope/Cosmic Origin Spectrograph, which cover the diagnostic-rich…

Astrophysics of Galaxies · Physics 2020-03-20 Timothy R. Miller , Nahum Arav , Xinfeng Xu , Gerard A. Kriss , Rachel J. Plesha

Recently, convincing evidence was found for extremely large X-ray absorption by column densities $> 10^{23} cm^{-2}$ in broad absorption line quasars. One consequence of this is that any soft X-ray emission from these QSOs would be the…

Astrophysics · Physics 2009-10-31 T. G. Wang , J. X. Wang , W. Brinkmann , M. Matsuoka

Accounting for ~20% of the total QSO population, Broad Absorption Line QSOs are still an unsolved problem in the AGN context. They present wide troughs in the UV spectrum, due to material with velocities up to 0.2 c toward the observer. The…

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
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