English
Related papers

Related papers: Molecular fraction limits in damped Lyman-alpha ab…

200 papers

We present results from a search for galaxies that give rise to damped Lyman alpha (DLA), subDLA, and Lyman limit system (LLS) absorption at redshifts 0.1 ~< z ~< 1 in the spectra of background quasars. The sample was formed from a larger…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Sandhya M. Rao , Michele Belfort-Mihalyi , David A. Turnshek , Eric M. Monier , Daniel B. Nestor , Anna M. Quider

We describe a search for redshifted [C II] in a z=3.137 damped Ly-alpha absorption system that has a large neutral hydrogen column density and which was controversially reported to be a source of CO emission, indicative of rapid…

Astrophysics · Physics 2007-05-23 Rob Ivison , A. P. Harrison , I. M. Coulson

We present a sample of 45 Damped Lyman-$\alpha$ system (DLA, \nhi\ $ \geq 2 \times 10^{20} {\rm cm}^{-2}$) counterparts (33 detections, 12 upper limits) which host gamma-ray bursts (GRB-DLAs) in order to investigate star-formation and…

We present the first D/H measurement in a damped Ly-alpha system at z_abs = 3.025 towards QSO 0347-3819 obtained from the UVES-VLT spectra. The DLA absorber has a metallicity of [Zn/H] = -1.25 and a relatively simple velocity structure,…

Astrophysics · Physics 2009-11-06 Sandro D'Odorico , Miroslava Dessauges-Zavadsky , Paolo Molaro

We present the results of a search for damped Lyman-alpha (DLA) systems in the Sloan Digital Sky Survey II (SDSS), Data Release 7. We use a fully automatic procedure to identify DLAs and derive their column densities. The procedure is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 P. Noterdaeme , P. Petitjean , C. Ledoux , R. Srianand

The APM multicolor survey for bright z > 4 objects, covering 2500 deg^2 of sky to m(R)~19, resulted in the discovery of thirty-one quasars with z > 4. High signal-to-noise optical spectrophotometry at 5A resolution has been obtained for the…

Astrophysics · Physics 2009-10-28 L. J. Storrie-Lombardi , R. G. McMahon , M. J. Irwin , C. Hazard

We are exploring the connection between damped Ly-alpha absorbers (DLAs) and Lyman break galaxies (LBGs) using deep -- (5sigma)=26 m_{AB}-- broad band imaging (UBVI) of four wide fields (0.25 sq. deg. each) obtained at the Kitt Peak 4-m…

Astrophysics · Physics 2007-05-23 Nicolas Bouche , James D. Lowenthal

The goal of the Complete Optical and Radio Absorption Line System (CORALS) survey is to quantify the potential impact on QSO absorber statistics from dust in intervening galaxies. Dust may introduce a selection bias in surveys which are…

Astrophysics · Physics 2009-11-10 Sara L. Ellison , Chris W. Churchill , Samantha A. Rix , Max Pettini

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

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 have used the Very Long Baseline Array to image 18 quasars with foreground damped Lyman-$\alpha$ systems (DLAs) at 327, 610 or 1420 MHz, to measure the covering factor $f$ of each DLA at or near its redshifted HI 21cm line frequency.…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 N. Kanekar , W. M. Lane , E. Momjian , F. H. Briggs , J. N. Chengalur

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

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 report the detection of HI 21 cm absorption from the $z=2.289$ damped Lyman-$\alpha$ system (DLA) towards TXS 0311+430, with the Green Bank Telescope. The 21 cm absorption has a velocity spread (between nulls) of $\sim 110$ km s$^{-1}$…

Astrophysics · Physics 2009-11-13 Brian A. York , Nissim Kanekar , Sara L. Ellison , Max Pettini

Simulations predict that circumgalactic hydrogen gas surrounding massive ($M_{\rm{halo}}^{z=1}=10^{12}-10^{13}\ M_{\odot}$) galaxies at $z\sim4$ may be predominantly neutral, and could produce damped Ly$\alpha$ absorbers (DLAs) along…

Astrophysics of Galaxies · Physics 2025-12-10 Alon Gurman , Amiel Sternberg , Shmuel Bialy , Rachel K. Cochrane , Jonathan Stern

We have obtained a moderate resolution spectrum of the quasar PKS 0528-250 with the Red Channel Spectrograph on the Multiple Mirror Telescope (MMT) in order to study a damped Lyman alpha absorption line system at z = 2.8115. We obtain a new…

Astrophysics · Physics 2016-08-30 Jian Ge , Jill Bechtold , Constance Walker , John , H. Black

We present a VLT/UVES spectrum of a proximate sub-damped Lyman-alpha (sub-DLA) system at z=2.65618 toward the quasar Q0331-4505 (z_qso=2.6785+/-0.0030). Absorption lines of O I, Si II, Si III, Si IV, C II, C III, C IV, Fe II, Al II, and O…

Astrophysics · Physics 2009-11-13 Andrew J Fox , Patrick Petitjean , Cédric Ledoux , Raghunathan Srianand

Using a spectral stacking technique we searched for the average \lya emission from high-z Damped \lya (DLA) galaxies detected in the Sloan Digital Sky Survey QSO spectra. We used a sample of 341 DLAs of mean redshift <z>= 2.86 and log N(HI)…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 H. Rahmani , R. Srianand , P. Noterdaeme , P. Petitjean

The XQ-100 survey provides optical and near infrared coverage of 36 blindly selected, intervening damped Lyman alpha systems (DLAs) at 2 < z < 4, simultaneously covering the MgII doublet at 2796A, 2803A, and the Ly-alpha transition. Using…

The Circum-Galactic Medium (CGM) can be probed through the analysis of absorbing systems in the line-of-sight to bright background quasars. We present measurements of the metallicity of a new sample of 15 sub-damped Lyman-$\alpha$ absorbers…