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Related papers: The ESI/KeckII Damped Lya Abundance Database

200 papers

We present the elemental abundance and H2 content measurements of a Damped Lyman-{\alpha} (DLA) system with an extremely large H i column density, log N(H i) (cm-2) = 22.0+/-0.10, at zabs = 3.287 towards the QSO SDSS J 081634+144612. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 R. Guimarães , P. Noterdaeme , P. Petitjean , C. Ledoux , R. Srianand , S. Lopez , H. Rahmani

We investigated abundance ratios along the profiles of six high-redshift Damped Lyman-alpha systems, three of them associated with H2 absorption, and derived optical depths in each velocity pixel. The variations of the pixel abundance…

Astrophysics · Physics 2009-11-11 E. Rodriguez , P. Petitjean , B. Aracil , C. Ledoux , R. Srianand

We present the results from an automated search for damped Lya (DLA) systems in the quasar spectra of Data Release 1 from the Sloan Digital Sky Survey (SDSS-DR1). At z~2.5, this homogeneous dataset has greater statistical significance than…

Astrophysics · Physics 2015-06-24 Jason X. Prochaska , Stephane Herbert-Fort

We present a study of ~100 high redshift (z~2-4) extremely strong damped Lyman-alpha systems (ESDLA, with N(HI)>0.5x10^22 cm^-2) detected in quasar spectra from the Baryon Oscillation Spectroscopic Survey SDSS-III DR11. We study the neutral…

Astrophysics of Galaxies · Physics 2014-07-01 P. Noterdaeme , P. Petitjean , I. Paris , Z. Cai , H. Finley , J. Ge , M. M. Pieri , D. G. York

We present a detailed analysis of a high resolution spectrum of the damped Ly$\alpha$ system at $z_{\rm abs}$~=~2.8112toward PKS~0528-250. The absorption redshift is slightly larger than the emission redshift of the quasar. We estimate the…

Astrophysics · Physics 2007-05-23 R. Srianand , P. Petitjean

We present the results from a damped Lya survey of the Sloan Digital Sky Survey, Data Release 3 based on over 500 new damped Lya systems at z>2.2. We measure the HI column density distribution f(N) and its zeroth and first moments (the…

Astrophysics · Physics 2008-11-26 Jason X. Prochaska , Stephane Herbert-Fort , Arthur M. Wolfe

We report the first discovery of a QSO damped Ly-alpha (DLA) system by the GALEX satellite. The system was initially identified as an MgII absorption-line system (z_abs=1.028) in the spectrum of SDSS QSO J0203-0910 (z_em=1.58). The presence…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Eric Monier , David Turnshek , Sandhya Rao , Anja Weyant

An accurate method to measure the abundance of high-redshift galaxies consists in the observation of absorbers along the line of sight toward a background quasar. Here, we present abundance measurements of 13 z>3 sub-Damped Lyman-alpha…

We present here a dataset of quasars observed with the Ultraviolet Visual Echelle Spectrograph (UVES) on the VLT and available in the ESO UVES Advanced Data Products archive. The sample is made up of a total of 250 high resolution quasar…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-16 Tayyaba Zafar , Attila Popping , Celine Peroux

We present the current status of ongoing searches for molecular hydrogen in high-redshift (1.8 < zabs <= 4.2) Damped Lyman-alpha systems (DLAs) capitalising on observations performed with the ESO Very Large Telescope (VLT) Ultraviolet and…

Astrophysics · Physics 2009-11-13 P. Noterdaeme , C. Ledoux , P. Petitjean , R. Srianand

Damped Ly$\alpha$ absorbers (DLAs) are the highest \HI\ column density (\NHI) absorption line systems detected in the spectra of background quasars. DLAs dominate the neutral gas content of the Universe ($\Omega_{\rm HI}$) and are used to…

Using a sample of 21 damped Lyman alpha systems (DLAs) and 35 sub-DLAs, we evaluate the D-index = EW / Delta v x 1000 from high resolution spectra of the MgII lambda 2796 profile. This sample represents an increase in sub-DLA D-index…

Astrophysics · Physics 2009-11-13 Sara L. Ellison , Michael T. Murphy , Miroslava Dessauges-Zavadsky

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

Recent high-resolution observations of metal absorption lines in high-redshift damped Ly-alpha systems have shown that Al III, a tracer of moderately-ionized gas, very often has a velocity structure indistinguishable from that of…

Astrophysics · Physics 2009-10-31 J. Christopher Howk , Kenneth R. Sembach

We derive the statistical properties of neutral gas at redshifts 0.11<z<1.65 from UV measurements of quasar Lyman alpha absorption lines corresponding to 369 MgII systems with $W^{\lambda2796}_{0} \ge 0.3$ \AA. In addition to the 41 damped…

Astrophysics of Galaxies · Physics 2017-08-23 Sandhya M. Rao , David A. Turnshek , Gendith M. Sardane , Eric M. Monier

We have discovered molecular hydrogen in a fourth quasar damped Ly-alpha system (hereafter DLA). The UVES spectrograph on the 8.2m ESO Kueyen telescope has allowed the detection of H2 in gas with low metallicity, Z/Z_solar ~= 10^{-2}, and…

Astrophysics · Physics 2007-05-23 S. A. Levshakov , P. Molaro , M. Centurion , S. D'Odorico , P. Bonifacio , G. Vladilo

We present the measured gas-phase metal column densities in 155 sub-damped Lyman alpha systems (subDLAs) with the aim to investigate the contribution of subDLAs to the chemical evolution of the Universe. The sample was identified within the…

We present the Damped Ly$\alpha$ Toolkit for automated detection and characterization of Damped Ly$\alpha$ absorbers (DLA) in quasar spectra. Our method uses quasar spectral templates with and without absorption from intervening DLAs to…

We use high resolution Eulerian hydrodynamics simulations to study kinematic properties of the low ionization species in damped Ly-alpha systems at redshift z=3. Our adaptive mesh refinement simulations include most key ingredients relevant…

Astrophysics · Physics 2009-11-13 Alexei O. Razoumov , Michael L. Norman , Jason X. Prochaska , Arthur M. Wolfe

We have obtained a high resolution, high S/N UVES spectrum of the bright QSO HE2243-6031 to analyze the damped Ly-alpha system (DLA) observed at z=2.33. The metallicity of this system is 1/12 solar at a neutral hydrogen column density of…

Astrophysics · Physics 2009-11-07 Sebastian Lopez , Dieter Reimers , Sandro D'Odorico , Jason X. Prochaska