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

200 papers

We estimate the intrinsic neutral gas density in Damped Lyman Alpha systems ($\Omega_{HI}^{(DLA)}$) in the redshift range $ 2.2 \lesssim z \lesssim 5$ from the DLA SDSS DR_3 sample of optically selected quasars. We take into account…

Astrophysics · Physics 2008-11-26 M. Trenti , M. Stiavelli

We present the largest homogeneous survey of $z>4.4$ damped Lyman-$\alpha$ systems (DLAs) using the spectra of 163 QSOs that comprise the Giant Gemini GMOS (GGG) survey. With this survey we make the most precise high-redshift measurement of…

We compare the properties of a sample of local (z=0) gas-rich galaxies studied in 21 cm emission to a sample of 13 low-redshift (z < 1) damped Lyman alpha (DLA) galaxies identified as the counterparts of low-redshift DLA systems found in…

Astrophysics · Physics 2007-05-23 David A. Turnshek , Sandhya M. Rao , Daniel B. Nestor

We present a comprehensive analysis of the damped Lya abundance database presented in the first paper of this series. This database provides a homogeneous set of abundance measurements for many elements including Si, Cr, Ni, Zn, Fe, Al, S,…

Astrophysics · Physics 2009-11-07 Jason X. Prochaska , Arthur M. Wolfe

We study the distribution of the star formation rate and metallicity of damped Lyman-alpha absorbers using cosmological SPH simulations of the Lambda cold dark matter model in the redshift range z=0-4.5. Our approach includes a…

Astrophysics · Physics 2009-11-07 Kentaro Nagamine , Volker Springel , Lars Hernquist

As large optical quasar surveys for damped Lya become a reality and the study of star forming gas in the early Universe achieves statistical robustness, it is now vital to identify and quantify the sources of systematic error. Because the…

Though observationally rare, damped Lya absorption systems dominate the mass density of neutral gas in the Universe. Eleven high redshift damped Lya systems covering 2.8<z<4.4 were discovered in 26 QSOs from the APM z>4 QSO Survey,…

Astrophysics · Physics 2016-06-08 L. J. Storrie-Lombardi , R. G. McMahon , M. J. Irwin

The formation and evolution of galaxies require large reservoirs of cold, neutral gas. The damped Lya systems (DLAs), seen in absorption towards distant quasars and gamma-ray bursts, are predicted to be the dominant reservoirs for this gas.…

Astrophysics of Galaxies · Physics 2015-10-28 Jeff Cooke , John O'Meara

Based on the disk galaxy formation theory within the framework of standard LCDM hierarchical picture, we selected modelled DLAs, according to their observational criterion, by Monte Carlo simulation with the random inclinations being…

Astrophysics · Physics 2015-06-24 J. L. Hou , C. G. Shu , S. Y. Shen , R. X. Chang , W. P. Chen , C. Q. Fu

Using Sloan Digital Sky Survey (SDSS) early data release spectra, we have identified 370 MgII absorption systems with MgII 2796 rest equivalent widths >= 1A and redshifts z=0.9-2.2. From our previous and ongoing HST UV spectroscopic…

Astrophysics · Physics 2009-11-10 Daniel B. Nestor , Sandhya M. Rao , David A. Turnshek , Daniel Vanden Berk

Any viable cosmological model must produce enough structure at early epochs to explain the amount of gas associated with high-redshift damped Ly$\alpha$ systems. We study the evolution of damped Ly$\alpha$ systems at redshifts $z\ge 2$ in…

Astrophysics · Physics 2009-10-30 Chung-Pei Ma , Edmund Bertschinger , Lars Hernquist , David H. Weinberg , Neal Katz

We present a sample of 33 damped Lyman alpha systems (DLAs) discovered in the Sloan Digital Sky Survey (SDSS) whose absorption redshifts (z_abs) are within 6000 km/s of the QSO's systemic redshift (z_sys). Our sample is based on 731 2.5 <…

Astrophysics · Physics 2009-11-13 David M. Russell , Sara L. Ellison , Chris R. Benn

Sub-damped Lyman alpha systems (subDLAs; HI column densities of 19.0<=logN(HI)<20.3) are rarely included in the cosmic HI census performed at redshifts z>=1.5, yet are expected to contribute significantly to the overall HI mass budget of…

Damped Ly-alpha Systems (DLAs), with N(HI)>2*10^20 cm^{-2}, observed in quasars have allowed us to quantify the chemical content of the Universe over cosmological scales. Such studies can be extended to lower N(HI), in the sub-DLA range…

We study the average Ly$\alpha$ emission associated with high-$z$ strong (log $N$(H I) $\ge$ 21) damped Ly$\alpha$ systems (DLAs). We report Ly$\alpha$ luminosities ($L_{\rm Ly\alpha}$) for the full as well as various sub-samples based on…

Astrophysics of Galaxies · Physics 2016-12-14 Ravi Joshi , Raghunathan Srianand , Pasquier Noterdaeme , Patrick Petitjean

We compare new observations on the kinematic characteristics of the damped Lya systems against results from numerical SPH simulations to test the predictions of hierarchical galaxy formation. This exercise is particularly motivated by…

Astrophysics · Physics 2009-11-07 Jason X. Prochaska , Arthur M. Wolfe

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 study the nature of damped Lya absorption (DLA) systems at z<=1 using a sample of 11 DLA galaxies, for which accurate redshift measurements are available. We demonstrate that the precision of photometric redshifts is sufficient for…

Astrophysics · Physics 2009-11-10 Hsiao-Wen Chen , Kenneth M. Lanzetta

We present a new study of the effects of quasar obscuration on the statistics of Damped Ly alpha (DLA) systems. We show that the extinction of any Galactic or extragalactic HI region increases with the column density of zinc with a turning…

Astrophysics · Physics 2009-11-10 Giovanni Vladilo , Celine Peroux

We investigate the properties of damped Ly{\alpha} absorption systems (DLAs) in semi-analytic models of galaxy formation, including partitioning of cold gas in galactic discs into atomic, molecular, and ionized phases with a molecular…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Michael Berry , Rachel S. Somerville , Marcel R. Haas , Eric Gawiser , Ari Maller , Gergo Popping , Scott C. Trager