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Related papers: The SDSS Damped Lya Survey: Data Release 1

200 papers

Hubble Space Telescope (HST) UV spectroscopy of 12 candidate low-redshift damped Lyman alpha (DLA) systems in 11 QSOs (z=0.103 in Q0054+144, z=0.969 and z=0.987 in Q0302-223, z=0.478 in Q0454-220, z=1.476 in Q1047+550, z=1.070 in Q1206+459,…

Astrophysics · Physics 2009-11-07 David A. Turnshek , Sandhya M. Rao

We present the results of a series of imaging and spectroscopic observations aimed at identifying and studying the galaxy responsible for the z = 3.38639 damped lya system in the z = 3.61 QSO Q0201+1120. We find that the DLA is part of a…

Astrophysics · Physics 2016-08-30 Sara L. Ellison , Max Pettini , Charles C. Steidel , Alice E. Shapley

We publish the Keck/HIRES and Keck/ESI spectra that we have obtained during the first 10 years of Keck observatory operations. Our full sample includes 42 HIRES spectra and 39 ESI spectra along 65 unique sightlines providing abundance…

Determining the spatial distribution and intrinsic physical properties of neutral hydrogen on cosmological scales is one of the key goals of next-generation radio surveys. We use the EAGLE galaxy formation simulations to assess the…

We present a brief overview of the ongoing Complete Optical and Radio Absorption Line System (CORALS) survey. We review the results of our survey for z>2.2 damped Lyman alpha systems (DLAs) and present the preliminary results of an extended…

We study metal abundances in the z=0.9313 damped Lya system observed in the two lines-of-sight, A and B, toward the gravitationally-lensed double QSO HE0512-3329. Spatially resolved STIS spectra constrain the neutral-gas column density to…

Astrophysics · Physics 2009-11-10 S. Lopez , D. Reimers , M. D. Gregg , L. Wisotzki , O. Wucknitz , A. Guzman

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

Quasar foreground damped absorbers, associated with HI-rich galaxies allow to estimate the neutral gas mass over cosmic time, which is a possible indicator of gas consumption as star formation proceeds. The DLAs and sub-DLAs are believed to…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-16 Tayyaba Zafar , Celine Peroux , Attila Popping , Bruno Milliard , Jean-Michel Deharveng , Stephan Frank

We use the average E(B-V) and ZnII column densities of a sample of z~1 CaII (3935, 3970) absorption line systems selected from the Sloan Digital Sky Survey (SDSS DR4) to show that on average, with conservative assumptions regarding…

Astrophysics · Physics 2009-11-11 Vivienne Wild , Paul Hewett , Max Pettini

We calculate the number of damped Lyman-alpha absorbers expected in various popular cosmological models as a function of redshift and compare our predictions with observed abundances. The Press-Schechter formalism is used to obtain the…

Astrophysics · Physics 2009-10-30 Jeffrey P. Gardner , Neal Katz , David H. Weinberg , Lars Hernquist

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 apply a physically motivated stellar feedback model to analyse the statistical properties of damped Lyman-alpha systems (DLAs) expected in the concordance cold dark matter (CDM) model. Our feedback model produces extended low-metallicity…

Astrophysics · Physics 2009-11-11 P. H. Johansson , G. Efstathiou

We use the Hubble Space Telescope (HST) archive of ultraviolet (UV) quasar spectroscopy to conduct the first blind survey for damped Ly-alpha absorbers (DLAs) at low redshift (z < 1.6). Our statistical sample includes 463 quasars with…

A new method is used to measure the physical conditions of the gas in damped Lyman-alpha systems (DLAs). Using high resolution absorption spectra of a sample of 80 DLAs, we are able to measure the ratio of the upper to lower fine-structure…

Astrophysics of Galaxies · Physics 2015-06-23 Marcel Neeleman , J. Xavier Prochaska , Arthur. M. Wolfe

We report the discovery of two damped Ly-alpha absorption-line systems (DLAs) near redshift z=1 along a single quasar sightline (Q1727+5302) with neutral hydrogen column densities of N(HI) = (1.45\pm0.15)\times10^{21} and…

We present results from a search for strong H2 absorption systems proximate to quasars (zabs~zem) in the Sloan Digital Sky Survey (SDSS) Data Release 14. The search is based on the Lyman-Werner band signature of damped H2 absorption lines…

Astrophysics of Galaxies · Physics 2019-07-03 P. Noterdaeme , S. Balashev , J. -K. Krogager , R. Srianand , H. Fathivavsari , P. Petitjean , C. Ledoux

The number of z ~ 1 damped Lyman alpha systems (DLAs, log N(HI) >= 20.3) per unit redshift is approximately 0.1, making them relatively rare objects. Large, blind QSO surveys for low redshift DLAs are therefore an expensive prospect for…

Astrophysics · Physics 2009-11-11 Sara L. Ellison

From the analysis of the near-UV spectrum of the QSO 2206-199, obtained with a long series of exposures with STIS on the HST, we deduce a value (D/H) = (1.65 +/- 0.35) x 10(-5) (1 sigma error) for the abundance of deuterium in the z(abs) =…

Astrophysics · Physics 2009-11-06 Max Pettini , David V. Bowen

We have completed spectroscopic observations using LRIS on the Keck 1 telescope of 30 very high redshift quasars, 11 selected for the presence of damped Ly-alpha absorption systems and 19 with redshifts z > 3.5 not previously surveyed for…

Astrophysics · Physics 2009-10-31 Lisa J. Storrie-Lombardi , Arthur M. Wolfe

We investigate Damped Ly-alpha absorbing galaxies (DLA galaxies) at low redshifts z<1 in the hierarchical structure formation scenario to clarify the nature of DLA galaxies because observational data of such galaxies mainly at low redshifts…

Astrophysics · Physics 2009-11-10 Katsuya Okoshi , Masahiro Nagashima