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Related papers: First stars in Damped Lyman Alpha systems

200 papers

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

We investigate the properties of Damped Lyman-alpha systems (DLAs) using high-resolution and large box-size cosmological hydrodynamical simulations of a LambdaCDM model. The numerical code used is a modification of GADGET-2 with a self…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Edoardo Tescari , Matteo Viel , Luca Tornatore , Stefano Borgani

In order to constrain the initial mass function (IMF) of the first generation of stars (Population III), we investigate the fragmentation properties of metal-free gas in the context of a hierarchical model of structure formation. We…

Astrophysics · Physics 2009-10-31 Volker Bromm , Paolo S. Coppi , Richard B. Larson

We present a galactic chemical evolution model which adopts updated prescriptions for all the main processes governing the dust cycle. We follow in detail the evolution of the abundances of several chemical species (C, O, S, Si, Fe and Zn)…

Astrophysics of Galaxies · Physics 2016-09-21 Lorenzo Gioannini , Francesca Matteucci , Giovanni Vladilo , Francesco Calura

We test the hypothesis that the host galaxies of long-duration gamma-ray bursts (GRBs) as well as quasar-selected damped Lyman-alpha (DLA) systems are drawn from the population of UV-selected star-forming, high-z galaxies (generally…

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…

Astrophysics · Physics 2007-05-23 Giovanni Vladilo

We study the formation of damped \lya and Lyman limit absorbers in a hierarchical clustering scenario using a gas dynamical simulation of an $\Omega = 1$, cold dark matter universe. In the simulation, these high column density systems are…

Astrophysics · Physics 2009-10-28 Neal Katz , David H. Weinberg , Lars Hernquist , Jordi Miralda-Escude

The metallicity in portions of high-redshift galaxies has been successfully measured thanks to the gas observed in absorption in the spectra of quasars, in the Damped Lyman-alpha systems (DLAs). Surprisingly, the global mean metallicity…

Astrophysics · Physics 2009-05-29 C. Peroux , V. P. Kulkarni , J. Meiring , R. Ferlet , P. Khare , J. T. Lauroesch , G. Vladilo , D. G. York

The XQ-100 survey has provided high signal-noise spectra of 100 redshift 3-4.5 quasars with the X-Shooter spectrograph. The metal abundances for 13 elements in the 41 damped Lyman alpha systems (DLAs) identified in the XQ-100 sample are…

Our knowledge of galactic chemical evolution is currently limited to observations of Milky Way stars and H II regions of nearby galaxies. Damped Lyman~$\alpha$ systems offer a new approach for tracking the evolution of normal galaxies from…

Astrophysics · Physics 2007-05-23 K Lipman , M Pettini , R Hunstead

We present the results of a long-slit K-band spectroscopic search for H-alpha emission from eight damped Ly-alpha absorbers (DLAs) at z>2 with the goal of measuring the star-formation rates in these systems. For each system we searched for…

The most metal-poor stars in dwarf spheroidal galaxies (dSphs) can show the nucleosynthetic patterns of one or a few supernovae. These supernovae could have zero metallicity, making metal-poor dSph stars the closest surviving links to…

Astrophysics of Galaxies · Physics 2012-11-12 Evan N. Kirby , Judith G. Cohen

Molecular hydrogen is quite underabundant in damped Lyman-alpha systems at high redshift, when compared to the interstellar medium near the Sun. This has been interpreted as implying that the gas in damped Lyman-alpha systems is warm. like…

Astrophysics · Physics 2009-11-07 H. Liszt

Recent observations have revealed that damped Ly$\alpha$ clouds (DLAs) host star formation activity. In order to examine if such star formation activity can be triggered by ionization fronts, we perform high-resolution hydrodynamics and…

Astrophysics · Physics 2008-11-26 Ilian T. Iliev , Hiroyuki Hirashita , Andrea Ferrara

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-08 Simeon Bird , Mark Vogelsberger , Martin Haehnelt , Debora Sijacki , Shy Genel , Paul Torrey , Volker Springel , Lars Hernquist

Details of processes through which galaxies convert their gas into stars need to be studied in order to obtain a complete picture of galaxy formation. One way to tackle these phenomena is to relate the HI gas and the stars in galaxies.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Celine Peroux , Nicolas Bouche , Varsha P. Kulkarni , Donald G. York , Giovanni Vladilo

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 use detailed Lyalpha radiative transfer calculations to further test the claim of Rauch et al. (2008) that they have detected spatially extended faint Lyalpha emission from the elusive host population of Damped Lyalpha Absorption systems…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-19 Luke A. Barnes , Martin G. Haehnelt

We discuss the recent Baryon Oscillation Spectroscopic Survey measurement of a rather high bias factor for the host galaxies/haloes of Damped Lyman-alpha Absorbers (DLAs), in the context of our previous modelling of the physical properties…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-06 Luke A. Barnes , Martin G. Haehnelt

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
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