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Related papers: The SDSS Damped Lya Survey: Data Release 3

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We have combined new high resolution UVES-VLT observations of a sample of four damped Ly-alpha systems (DLAs) at redshifts between z_abs = 1.7-2.5 with the existing HIRES-Keck spectra to undertake a comprehensive study of their physical…

Astrophysics · Physics 2009-11-07 M. Dessauges-Zavadsky , J. X. Prochaska , S. D'Odorico

(Abridged) We detect the large-scale structure of Lya emission in the Universe at redshifts z=2-3.5 by measuring the cross-correlation of Lya surface brightness with quasars in SDSS/BOSS. We use a million spectra targeting Luminous Red…

The similarity between observed velocity structures of Al III and singly ionized species in damped Lyman-alpha systems (DLAs) suggests the presence of ionized gas in the regions where most metal absorption lines are formed. A simplified…

Astrophysics · Physics 2009-10-31 Yuri I. Izotov , Daniel Schaerer , Corinne Charbonnel

We study the formation of damped \lya and Lyman limit absorbers in a hierarchical clustering scenario using a gas dynamical simulation of an $\Omega = 1$, cold dark matter universe. In the simulation, these high column density systems are…

Astrophysics · Physics 2009-10-28 Neal Katz , David H. Weinberg , Lars Hernquist , Jordi Miralda-Escude

The Lyman-alpha (Lya) emission line is the primary observational signature of star-forming galaxies at the highest redshifts, and has enabled the compilation of large samples of galaxies with which to study cosmic evolution. The resonant…

The cross-section of sky occupied by a particular neutral hydrogen column density provides insight into the nature of Lyman-alpha absorption systems. We have measured this column density distribution at z=0 using 21-cm HI emission from a…

Astrophysics · Physics 2007-05-23 Emma Ryan-Weber , Rachel Webster , Lister Staveley-Smith

A new method is presented for recovering the abundances of Damped Ly alpha systems (DLAs) taking into account the effects of dust depletion. For the first time, possible variations of the chemical composition of the dust are taken into…

Astrophysics · Physics 2009-11-07 G. Vladilo

We present Keck/HIRES abundance measurements and metal-line kinematic profiles of the damped Lyman alpha systems (DLAs) towards the quasars Q0933+733 (z_abs=1.479) and Q0948+433 (z_abs=1.233). These two DLAs have among the five highest HI…

Astrophysics · Physics 2009-11-10 Sandhya M. Rao , Jason X. Prochaska , J. Christopher Howk , Arthur M. Wolfe

We combine cosmological, hydrodynamical simulations with accurate radiative transfer corrections to investigate the relation between strong HI absorbers (N_HI >~ 10^17 /cm^2) and galaxies at redshift z = 3. We find a strong anti-correlation…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-19 Alireza Rahmati , Joop Schaye

We used the photometric database of the Sloan Digital Sky Survey (SDSS) to estimate the reddening of 13 SDSS quasars selected on the basis of the presence of zinc absorption lines in an intervening Damped Ly alpha (DLA) system. In 5 of…

Astrophysics · Physics 2008-11-26 G. Vladilo , M. Centurion , S. A. Levshakov , C. Peroux , P. Khare , V. P. Kulkarni , D. G. York

We present a spectroscopically confirmed sample of Lyman alpha emitting galaxies (LAEs) at z ~ 4.5 in the Extended Chandra Deep Field South (ECDFS), which we combine with a sample of z ~ 4.5 LAEs from the Large Area Lyman Alpha (LALA)…

This paper presents chemical abundance measurements for 12 new z>3 damped Lya systems discovered toward five quasars from the Palomar Sky Survey. We determine HI column densities from profile fits to the observed damped Lya profiles and…

Astrophysics · Physics 2009-11-07 Jason X. Prochaska , Sandra Castro , S. G. Djorgovski

We present a study of the early build-up of dust in high redshift galaxies. The study is based on the analysis of 38 Damped Ly alpha systems (DLAs) for which we derive the fraction of iron atoms in dust form, f_{Fe}. The sample is…

Astrophysics · Physics 2009-11-10 Giovanni Vladilo

We present 4 new measurements of nitrogen abundances and one upper limit in damped Lyman alpha absorbers (DLAs) obtained by means of high resolution (FWHM \~ 7 km/s) UVES/VLT spectra. In addition to these measurements we have compiled data…

Astrophysics · Physics 2011-05-23 M. Centurion , P. Molaro , G. Vladilo , C. Peroux , S. A. Levshakov , V. D'Odorico

We probe the physical conditions in high redshift galaxies, specifically, the Damped Lyman-alpha Systems (DLAs) using neutral carbon (CI) fine structure lines and molecular hydrogen (H2). We report five new detections of CI and analyze the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Regina A. Jorgenson , Arthur M. Wolfe , J. Xavier Prochaska

Spectra of high redshift QSOs show deep Gunn-Peterson absorptions on the blue sides of the \Lya emissions lines. They can be decomposed into components called \Lya leaks, defined to be emissive regions in complementary to otherwise…

Astrophysics · Physics 2009-11-13 Jiren Liu , Hongguang Bi , Li-Zhi Fang

The gas-phase and stellar metallicities have proven to be important parameters to constrain the star formation history of galaxies. However, HII regions associated with recent star-formation may not have abundances typical for the galaxy as…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Celine Peroux , Varsha P. Kulkarni , Donald G. York

We take a fresh look at the abundance of nitrogen in DLAs with oxygen abundances between 1/10 and 1/100 of solar. This is a metallicity regime poorly sampled in the local universe and where QSO absorbers may hold clues to both the…

Astrophysics · Physics 2009-11-07 Max Pettini , Sara L. Ellison , Jacqueline Bergeron , Patrick Petitjean

We study the H2 molecular content in high redshift damped Lyman-alpha systems (DLAs) as a function of the HI column density. We find a significant increase of the H2 molecular content around log N(HI) (cm^-2)~21.5-22, a regime unprobed…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-10 P. Noterdaeme , P. Petitjean , R. Srianand

Aims. The aim of this work is to study the contribution of the Ly-a emitters (LAE) to the star formation rate density (SFRD) of the Universe in the interval 2<z<6.6. Methods. We assembled a sample of 217 LAE from the Vimos-VLT Deep Survey…

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