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Related papers: First detection of CO in a high-redshift DLA

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We present the results from the optical component of a survey for damped Lyman-alpha systems (DLAs) towards radio-loud quasars. Our quasar sample is drawn from the Texas radio survey with the following primary selection criteria: z_em >…

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

We present the results of a systematic search for molecular hydrogen (H2) in low redshift ($ 0.05 \lesssim z \lesssim 0.7$) DLAs and sub-DLAs with $N(HI) \gtrsim 10^{19.0}$ cm$^{-2}$, in the archival HST/COS spectra. Our core sample is…

Astrophysics of Galaxies · Physics 2015-03-10 Sowgat Muzahid , Raghunathan Srianand , Jane Charlton

Spectroscopy of QSO absorption lines provides essential observational input for the study of nucleosynthesis and chemical evolution of galaxies at high redshift. But new observations may indicate that present chemical abundance data are…

Astrophysics · Physics 2007-05-23 R. Quast , D. Reimers , A. Smette , O. Garcet , C. Ledoux , S. Lopez , L. Wisotzki

We report the identification of a very metal-poor damped Lyman-alpha system (DLA) at z_abs = 3.067295 that is modestly carbon-enhanced, with an iron abundance of ~1/700 solar ([Fe/H] = -2.84) and [C,O/Fe] ~ +0.6. Such an abundance pattern…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Ryan Cooke , Max Pettini , Michael Murphy

(ABRIDGED) We present a study of the highly ionized gas (plasma) associated with damped Lyman-alpha (DLA) systems at z=2.1-3.1. We search for O VI absorption and corresponding Si IV, C IV, and N V in a Very Large…

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

(Abridged for arXiv) We report the discovery of an unusual, extremely dust-rich and metal-strong damped \lya absorption system (DLA) at a redshift $z_{a}=2.4596$ toward the quasar SDSS J115705.52+615521.7 (hereafter J1157+6155) with an…

We investigate the CO excitation and interstellar medium (ISM) conditions in a cold gas mass-selected sample of 22 star-forming galaxies at $z=0.46-3.60$, observed as part of the ALMA Spectroscopic Survey in the Hubble Ultra Deep Field…

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

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 Damped Ly-alpha (DLA) absorber at redshift z_abs=4.383 observed toward QSO BRI 1202-0725 is studied by means of high resolution (FWHM ~ 7 km/s) VLT-UVES spectra. We refine a previously determined Si abundance and derive with confidence…

Astrophysics · Physics 2014-10-13 Valentina D'Odorico , Paolo Molaro

We have used archival far-ultraviolet spectra from observations made by HST/STIS and FUSE to determine the column densities and rotational excitation temperatures for CO and H2, respectively, along the lines of sight to 23 Galactic O and B…

Astrophysics · Physics 2009-01-19 Eric B. Burgh , Kevin France , Stephan R. McCandliss

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 report the discovery of a "super-damped" Lyman-alpha absorber at $z_{abs}=2.2068$ toward QSO Q1135-0010 in the Sloan Digital Sky Survey, and follow-up VLT UVES spectroscopy. Voigt profile fit to the DLA line indicates log $N_{\rm H I} =…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-23 Varsha P. Kulkarni , Joseph Meiring , Debopam Som , Celine Peroux , Donald G. York , Pushpa Khare , James T. Lauroesch

Damped Lyman-alpha systems seen in spectra of background quasars are generally thought to represent high redshift counterparts of present-day galaxies. We summarize observations of heavy element abundances in damped Lyman-alpha systems. The…

Astrophysics · Physics 2007-05-23 Limin Lu , Wallace L. W. Sargent , Thomas A. Barlow

We report on a sensitive search for redshifted H$\alpha$ line-emission from three high-metallicity damped Ly$\alpha$ absorbers (DLAs) at $z \approx 2.4$ with the Near-infrared Integral Field Spectrometer (NIFS) on the Gemini-North…

Astrophysics of Galaxies · Physics 2015-06-23 Wei-Hao Wang , Nissim Kanekar , J. Xavier Prochaska

We present the results of a survey for damped (DLA, log N(H I) > 20.3) and sub-damped Lyman-? systems (19.5 < log N(H I) < 20.3) at z > 2.55 along the lines-of-sight to 77 quasars with emission redshifts in the range 4 < zem < 6.3.…

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 the study of CI/H$_2$ relative abundance in the diffuse cold neutral medium. Using the chemical and thermal balance model we calculated the dependence of CI/H$_2$ on the main parameters of the medium: hydrogen number density,…

Astrophysics of Galaxies · Physics 2024-02-02 Sergei Balashev , Daria Kosenko

In the last years, progress has been very rapid in the domain of molecules at high redshift, and we know in better detail now the molecular and dust content in several systems beyond z=1 and up to z = 5. The first discovery in 1992 by Brown…

Astrophysics · Physics 2016-08-30 F. Combes

We present the first results from the Complete Optical and Radio Absorption Line System (CORALS) survey for Damped Lyman Alpha (DLA) systems based on a radio-selected sample of quasars. We find that the number density and neutral gas…

Astrophysics · Physics 2007-05-23 Sara L. Ellison , Lin Yan , Isobel M. Hook , Max Pettini , Jasper V. Wall , Peter Shaver