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Related papers: On the Origin of the Clustered QSO Metal Absorptio…

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We investigate the heavy element QSO absorption systems caused by gas condensations at high redshift which evolve into galaxies with circular velocity of 100 to 200 km/s at the present epoch. Artificial QSO spectra were generated for a…

Astrophysics · Physics 2009-10-28 Martin Haehnelt , Matthias Steinmetz , Michael Rauch

We present the first large sample of absorption systems in paired QSOs consisting of 691 absorption systems in the spectra of 310 QSOs including 170 pairings. All these absorption systems have metal lines, usually C IV or Mg II. We see 17…

Recent observations have shown that (some) metal line absorption systems in QSO spectra arise from gas in galactic halos with radii much larger than the optical radii of galaxies. We show that the observed galaxy-absorber connections are…

Astrophysics · Physics 2007-05-23 H. J. Mo

We report the detection of a significant clustering signal on scales $\Delta v < 300$ km/s, for a sample of 71 C IV absorbers. This result confirms previous findings and, together with data at lower column density, it points to a trend of…

Astrophysics · Physics 2007-05-23 Valentina D'Odorico

We explore the hypothesis that clouds detected in quasar absorption line systems are falling at a terminal velocity toward the center of high redshift gaseous galactic halos. Since both the ionization level and terminal velocity of halo…

Astrophysics · Physics 2007-05-23 Robert A. Benjamin

We examine the line-of-sight clustering of QSO heavy-element absorption-line systems, using a new measure of clustering, called the reduced second moment measure, that directly measures the mean over-density of absorbers. While closely…

Astrophysics · Physics 2009-10-30 Jean M. Quashnock , Michael L. Stein

Winds from star-forming galaxies provide the most promising explanation for the enrichment of the intergalactic medium with heavy elements. Theoretical and observational arguments indicate that the pollution may have occurred at z > 6;…

Astrophysics · Physics 2008-11-26 Steven Furlanetto , Abraham Loeb

This paper provides a general reference for deriving the ionizations and metal abundances for absorption-line clouds in photoionization equilibrium with a QSO spectrum. The results include a quantitative assessment of the theoretical…

Astrophysics · Physics 2009-10-30 Fred Hamann

Using Voigt-profile-fitting procedures on Keck HIRES spectra of nine QSOs we identify 1099 CIV absorber components clumped in 201 systems outside the Lyman forest over 1.6 < z < 4.4. With associated SiIV, CII, SiII and NV where available we…

Astrophysics of Galaxies · Physics 2015-05-27 Alec Boksenberg , Wallace L. W. Sargent

We present new GHRS observations of Lyman alpha absorption lines associated with a group of galaxies towards the QSO 1545+2101. We have identified eight distinct Lyman alpha absorption features in the spectrum of QSO 1545+2101 at a mean…

Astrophysics · Physics 2009-10-31 A. Ortiz-Gil , K. M. Lanzetta , J. K. Webb , X. Barcons , A. Fernandez-Soto

We present images and spectroscopy of objects close to the sightline of Q2302+029 in order to search for galaxies responsible for the remarkable z=0.7 high-ionization absorption line system found by Jannuzi et al (1996). This system shows…

Astrophysics · Physics 2009-10-31 David V. Bowen , Raul Jimenez , Edward B. Jenkins , Max Pettini

Recent detailed studies of Narrow Absorption Line (NAL) systems in QSO-spectra have revealed that at least 50% of QSOs have NALs associated with the central engine, and in most cases they are found to be outflowing. Will studies of NALs…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Vivienne Wild

We have analyzed the clustering of C IV absorption line systems in an extensive new catalog of heavy element QSO absorbers. The catalog permits exploration of clustering over a large range in both scale (from about 1 to over 300 Mpc) and…

Astrophysics · Physics 2009-05-29 Jean M. Quashnock , Daniel E. Vanden Berk , Donald G. York

During five decades astronomers have been puzzled by the presence of strong absorption features including metal lines, observed in the optical and ultraviolet spectra of quasars, signalling in- and outflowing gas winds with relative…

Astrophysics of Galaxies · Physics 2017-07-19 Peter Barthel , Pece Podigachoski , Belinda Wilkes , Martin Haas

There exists a significant population of broad line, z~2 QSOs which have heavily absorbed X-ray spectra. Follow up observations in the submillimetre show that these QSOs are embedded in ultraluminous starburst galaxies, unlike most…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 M. J. Page , F. J. Carrera , J. A. Stevens , J. Ebrero , A. J. Blustin

For the energy absorption of atomic clusters as a function of the laser pulse duration we find a similar behavior as it has been observed for metallic clusters [K\"oller et al., Phys. Rev. Lett. {\bf 82}, 3783 (1999)]. In both situations…

Atomic and Molecular Clusters · Physics 2007-05-23 Christian Siedschlag , Jan M Rost

Intrinsic emission and absorption lines of QSOs provide several independent probes of the metal abundances in QSO environments. They indicate that the metallicities are typically solar or higher out to redshifts z > 4. These results support…

Astrophysics · Physics 2007-05-23 Fred Hamann

The broad absorption lines (BALs) of QSOs indicate abundances of heavy elements, relative to hydrogen, that are 1 to 2 orders of magnitude higher than the solar values. In at least one QSO, an especially large enhancement of phosphorus is…

Astrophysics · Physics 2009-10-28 Gregory A. Shields

We present the results of a search for metal absorption lines in the spectra of background QSOs whose sightlines pass close to foreground QSOs. We detect MgII(2796,2803) absorption in Sloan Digital Sky Survey (SDSS) spectra of four z>1.5…

We present here new GHRS observations of Lyman-alpha absorption lines associated with groups or clusters toward the QSOs 1545+2101 and 0850+4400. In the first case we have identified at least eight distinct Lyman-alpha absorption features,…

Astrophysics · Physics 2007-05-23 A. Ortiz-Gil , K. M. Lanzetta , J. K. Webb , X. Barcons
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