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相关论文: DLAs and Galaxy Formation

200 篇论文

We use a cosmological hydrodynamic simulation of a cold dark matter universe to investigate theoretically the relationship between high redshift galaxies and the Lyman=alpha forest at redshift z=3. Galaxies in the simulation are surrounded…

天体物理学 · 物理学 2016-08-30 Rupert A. C. Croft , Lars Hernquist , Volker Springel , Michael Westover , Martin White

A comprehensive analysis of 355 high-quality WSRT HI 21-cm line maps of nearby galaxies shows that the properties and incident rate of Damped Lyman-alpha (DLA) absorption systems observed in the spectra of high redshift QSOs are in good…

天体物理学 · 物理学 2009-11-13 M. A. Zwaan , J. M. van der Hulst , F. H. Briggs , M. A. W. Verheijen , E. V. Ryan-Weber

Lyman limit and damped Lyman-alpha absorption systems probe the distribution of collapsed, cold gas at high redshift. Numerical simulations that incorporate gravity and gas dynamics can predict the abundance of such absorbers in…

天体物理学 · 物理学 2009-10-28 Jeffrey P. Gardner , Neal Katz , Lars Hernquist , David H. Weinberg

Studies of elemental abundances are a fundamental tool for unveiling the nature of the high-redshift (proto-)galaxies associated to Damped Ly alpha systems (DLAs). The present contribution analyses the impact of dust and ionization effects…

天体物理学 · 物理学 2007-05-23 Giovanni Vladilo

We have identified galaxies near two quasars which are at the redshift of damped Lyman-alpha (DLA) systems in the UV spectra of the quasars. Both galaxies are actively forming stars. One galaxy has a luminosity close to the break in the…

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…

星系天体物理 · 物理学 2014-07-01 P. Noterdaeme , P. Petitjean , I. Paris , Z. Cai , H. Finley , J. Ge , M. M. Pieri , D. G. York

We present results from a survey of galaxies in the fields of six z>3 Damped Lyman alpha systems (DLAs) using the Multi Unit Spectroscopic Explorer (MUSE) at the Very Large Telescope (VLT). We report a high detection rate of up to ~80% of…

We use cosmological hydrodynamical simulations including star formation and metal enrichment to study the evolution of the chemical properties of galaxy-like objects at high redshift in the range $0.25<z< 2.35$ in a hierarchical clustering…

天体物理学 · 物理学 2009-11-06 P. B. Tissera , D. G. Lambas M. B. Mosconi , S. A. Cora

We study the nature of Damped Lyman -Alpha systems (DLAs) by means of a comparison between observed abundances and models of chemical evolution of galaxies of different morphological type. In particular, we compare for the first time the…

天体物理学 · 物理学 2009-11-07 F. Calura , F. Matteucci , G. Vladilo

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…

天体物理学 · 物理学 2007-05-23 Nicolas Bouche , James D. Lowenthal

Previously we have shown that it is possible to account for the kinematic properties of damped Lyman alpha systems (DLAS) in the context of semi-analytic models. In these models, hierarchical structure formation is approximated by…

天体物理学 · 物理学 2007-05-23 Ariyeh H. Maller , Rachel S. Somerville , Jason X. Prochaska , Joel R. Primack

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…

天体物理学 · 物理学 2009-11-10 Hsiao-Wen Chen , Kenneth M. Lanzetta

We present results from an efficient, non-traditional survey to discover damped Lyman-alpha (DLA) absorption-line systems with neutral hydrogen column densities N(HI)>2x10^{20} atoms cm^{-2} and redshifts z<1.65. Contrary to previous…

天体物理学 · 物理学 2007-05-23 Sandhya Rao

We present optical and near-infrared ground-based imaging results on four low-redshift damped Ly-alpha (DLA) galaxies. The corresponding DLA systems were discovered in our HST spectroscopic surveys for DLA lines in known strong MgII…

Essentially all high-redshift galaxies show evidence for strong large-scale outflows that should have a profound effect on the structure and kinematics of both the galaxies themselves and their environment. The interstellar absorption…

天体物理学 · 物理学 2009-11-07 Joop Schaye

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)…

宇宙学与河外天体物理 · 物理学 2015-05-19 H. Rahmani , R. Srianand , P. Noterdaeme , P. Petitjean

The damped and sub-damped Lyman alpha systems (DLAs and sub-DLAs) traced in absorption against bright background quasars represent the main reserve of neutral hydrogen at high redshifts. We used the archival Very Large Telescope (VLT)…

星系天体物理 · 物理学 2018-08-15 Waqas Bashir , Tayyaba Zafar , Fazeel M. Khan , Farrukh Chishtie

The hypothesis that the Damped Ly-alpha systems (DLAs) are large, galactic disks (Milky Way sized) is tested by confronting predictions of models of the formation and evolution of (large) disk galaxies with observations, in particular the…

天体物理学 · 物理学 2009-10-31 Jesper Sommer-Larsen

We examine the abundance, clustering and metallicity of Damped Lyman-alpha Absorbers (DLAs) in a suite of hydrodynamic cosmological simulations using the moving mesh code AREPO. We incorporate models of supernova and AGN feedback, as well…

宇宙学与河外天体物理 · 物理学 2015-01-08 Simeon Bird , Mark Vogelsberger , Martin Haehnelt , Debora Sijacki , Shy Genel , Paul Torrey , Volker Springel , Lars Hernquist

In order to interpret H2 (molecular hydrogen) quasar absorption line observations of damped Ly-alpha systems (DLAs) and sub-DLAs, we model their H2 abundance as a function of dust-to-gas ratio, including H2 self-shielding and dust…

天体物理学 · 物理学 2009-11-10 H. Hirashita , A. Ferrara