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Related papers: Abundances in Damped Ly-alpha Galaxies

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A remarkably small scatter in the N/O ratios for the HII regions in low-metallicity blue compact galaxies (BCG) has been found recently. It lead to the conclusion that N and O are both produced by massive stars. Conversely, the N/Si ratios…

Astrophysics · Physics 2007-05-23 L. S. Pilyugin

Hydrogen Lyman-$\alpha$ (Ly$\alpha$) emission has been one of the major observational probes for the high redshift universe, since the first discoveries of high-$z$ Ly$\alpha$ emitting galaxies in the late 1990s. Due to the strong…

Astrophysics of Galaxies · Physics 2020-12-16 Masami Ouchi , Yoshiaki Ono , Takatoshi Shibuya

We investigate stellar elemental abundance patterns at z = 0 in 8 low-mass (M_* = 10^6 - 10^9 M_sun) galaxies in the Feedback in Realistic Environments (FIRE-2) cosmological simulations. Using magnesium (Mg) as a representative…

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 have collected an heterogeneous sample of galaxies at redshifts 0.001<z<3.35 with the aim of exploring the evolution of the physical parameters and of the element abundances calculated by modelling the observed spectra. The evolution…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-22 M. Contini

The results of a new spectroscopic survey of 66 $z \simgt 4$ quasars for Damped Lyman-alpha absorption systems are presented. The search led to the discovery of 30 new DLA candidates which are analysed in order to compute the comoving mass…

Astrophysics · Physics 2009-10-31 Celine Peroux , Mike J. Irwin , Richard G. McMahon , Lisa J. Storrie-Lombardi

One of the major conundrums in contemporary extragalactic astrophysics is the apparent overabundance of a remarkable population of UV-bright galaxies at redshifts $z\gtrsim 9$. We analyse galaxies spectroscopically observed by JWST/NIRSpec…

Chemical abundances of stellar streams can be used to determine the nature of a stream's progenitor. Here we study the progenitor of the recently discovered Leiptr stellar stream, which was previously suggested to be a tidally disrupted…

We report on the results of a search for CO(3-2) emission from the galaxy counterpart of a high-metallicity Damped Ly-alpha Absorber (DLA) at z=2.5832 towards the quasar Q0918+1636. We do not detect CO emission from the previously…

We report the detection, both in line and continuum emission, of a galaxy responsible for a damped Ly-alpha absorption (DLA) system at z=3.15 projected 2.3 arcsec from QSO 2233+131. The star formation rate implied by both the Ly-alpha and…

Astrophysics · Physics 2016-08-30 M. A. Pahre , S. G. Djorgovski , J. Bechtold , R. Elston

We study the dust depletion pattern in eight well separated components of the z=1.973, logN(HI)=20.83, damped Lyman-alpha system toward Q0013-004, four of which have detectable H2 absorption. The apparent correlation between the abundance…

Astrophysics · Physics 2009-11-07 Patrick Petitjean , R. Srianand , Cédric Ledoux

We present the first ever detection of Cobalt in a Damped Lyman Alpha system (DLA) at z = 1.92. In addition to providing important clues to the star formation history of these high redshift galaxies, we discuss how studying the Co abundance…

Astrophysics · Physics 2009-11-06 Sara L. Ellison , Sean G. Ryan , Jason X. Prochaska

We construct a simple, robust model of the chemical evolution of galaxies from high to low redshift, and apply it to published observations of damped Lyman-alpha quasar absorption line systems (DLAs). The elementary model assumes quiescent…

Astrophysics · Physics 2009-10-31 G. P. Mathlin , A. C. Baker , D. K. Churches , M. G. Edmunds

Oxygen abundances of 67 dwarf stars in the metallicity range -1.6<[Fe/H]<-0.4 are derived from a non-LTE analysis of the 777 nm O I triplet lines. These stars have precise atmospheric parameters measured by Nissen and Schuster, who find…

Solar and Stellar Astrophysics · Physics 2015-06-11 I. Ramirez , J. Melendez , J. Chaname

Le Brun et al. (1997) presented the first identifications of the galaxies giving rise to 7 intermediate redshift damped Ly-alpha (DLA) absorption systems. Here, we study the gravitational lensing properties of these foreground galaxies…

Astrophysics · Physics 2007-05-23 Vincent Le Brun , Alain Smette , Jean Surdej , Jean-Francois Claeskens

We have searched the Sloan Digital Sky Survey Data Release 12 for ghostly Damped Ly$\alpha$ (DLA) systems. These systems, located at the redshift of the quasars, show strong absorption from low-ionization atomic species but reveal no HI…

Astrophysics of Galaxies · Physics 2020-01-15 Hassan Fathivavsari

We present the detection of Ly-alpha, [OIII] and H-alpha emission associated with an extremely strong DLA system (N(HI) = 10^22.10 cm^-2) at z=2.207 towards the quasar SDSS J113520-001053. This is the largest HI column density ever measured…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 P. Noterdaeme , P. Laursen , P. Petitjean , S. D. Vergani , M. -J. Maureira , C. Ledoux , J. P. U. Fynbo , S. López , R. Srianand

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 analyze extant data of Al++, Al+ and other low ions with the aim of studying the ionization properties of Damped Ly alpha systems (DLAs) from the analysis of the ratio R(Al++/Al+) = N(Al++)/N(Al+). We find good correlations…

We study the H2 molecular content in high redshift damped Lyman-alpha systems (DLAs) as a function of the HI column density. We find a significant increase of the H2 molecular content around log N(HI) (cm^-2)~21.5-22, a regime unprobed…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-10 P. Noterdaeme , P. Petitjean , R. Srianand
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