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Related papers: First Detection of NaI D lines in High-Redshift Da…

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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 two damped Ly-alpha absorption-line systems (DLAs) near redshift z=1 along a single quasar sightline (Q1727+5302) with neutral hydrogen column densities of N(HI) = (1.45\pm0.15)\times10^{21} and…

We present observations of CaII, ZnII, and CrII absorption lines in 16 DLAs and 6 subDLAs at 0.6 < z < 1.3, obtained for the dual purposes of: (i) clarifying the relationship between DLAs and absorbers selected via strong CaII lines, and…

Astrophysics · Physics 2009-11-13 Daniel Nestor , Max Pettini , Paul Hewett , Sandhya Rao , Vivienne Wild

A study of the absorption systems toward the gravitationally lensed quasar APM 08279+5255 is presented. Most of the MgII systems in the redshift range 1.2-2.07, although saturated, show large residuals at the bottom of the lines. The most…

Astrophysics · Physics 2007-05-23 Patrick Petitjean , Bastien Aracil , R. Srianand , Rodrigo Ibata

1.02-1.16 micron spectra (R ~ 7,000) of the gravitationally lensed QSO APM 08279+5255 at z_em=3.911 were obtained during the commissioning run of IRCS, the 1-5 micron near-infrared camera and spectrograph for the Subaru 8.2 m Telescope.…

Astrophysics · Physics 2009-11-07 Naoto Kobayashi , Hiroshi Terada , Miwa Goto , Alan Tokunaga

We study a sample of 17 z>1.5 absorbers selected based on the presence of strong CI absorption lines in SDSS spectra and observed with the ESO-VLT spectrograph X-shooter. We derive metallicities, depletion onto dust, and extinction by dust,…

We present new imaging and spectroscopic observations of the fields of five QSOs with very strong intervening CaII absorption systems at redshifts z<0.5 selected from the Sloan Digital Sky Survey. Recent studies of these very rare absorbers…

Quasar damped Ly-alpha (DLA) absorption line systems with redshifts z<1.65 are used to trace neutral gas over approximately 70 per cent of the most recent history of the Universe. However, such systems fall in the UV and are rarely found in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 David A. Turnshek , Eric M. Monier , Sandhya M. Rao , Timothy S. Hamilton , Gendith M. Sardane , Ryan Held

We use the average E(B-V) and ZnII column densities of a sample of z~1 CaII (3935, 3970) absorption line systems selected from the Sloan Digital Sky Survey (SDSS DR4) to show that on average, with conservative assumptions regarding…

Astrophysics · Physics 2009-11-11 Vivienne Wild , Paul Hewett , Max Pettini

The Damped Lyman-alpha systems (DLAs), seen in absorption in the spectrum of quasars, are believed to contain a large fraction of the neutral gas in the Universe. Paradoxically, these systems are more difficult to observe at z_abs<1.7,…

Astrophysics · Physics 2009-11-10 Celine Peroux , Jean-Michel Deharveng , Vincent Le Brun , Stefano Cristiani

We present the results of a search for cold gas at high redshift along QSO lines-of-sight carried out without any a priori assumption on the neutral atomic-hydrogen (HI) content of the absorbers. To do this, we systematically looked for…

Astrophysics of Galaxies · Physics 2015-07-22 C. Ledoux , P. Noterdaeme , P. Petitjean , R. 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…

Using Sloan Digital Sky Survey (SDSS) early data release spectra, we have identified 370 MgII absorption systems with MgII 2796 rest equivalent widths >= 1A and redshifts z=0.9-2.2. From our previous and ongoing HST UV spectroscopic…

Astrophysics · Physics 2009-11-10 Daniel B. Nestor , Sandhya M. Rao , David A. Turnshek , Daniel Vanden Berk

We present a spectroscopic and imaging study of the z=0.558 MgII absorption system towards the BL Lac PKS 0118-272. At the absorber redshift we detect lines of the low ionization species MgI, MgII, CaII, TiII, MnII, and FeII. The column…

Astrophysics · Physics 2007-05-23 G. Vladilo , M. Centurion , R. Falomo , P. Molaro

We present ten metallicity measurements for quasar absorbers near $z=1.2$ that were selected for having unusually significant ZnII absorption in their SDSS spectra. Follow-up UV space spectroscopy of the Ly$\alpha$ region shows that all ten…

Astrophysics of Galaxies · Physics 2018-12-19 Eric M. Monier , David A. Turnshek , Sandhya M. Rao , Gendith M. Sardane , Daniel Burdette

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 present results of our HST Cycle 11 Survey for low-redshift (z<1.65) DLAs in the UV spectra of quasars selected from the SDSS Early Data Release. These quasars have strong intervening MgII-FeII systems which are known signatures of high…

Astrophysics · Physics 2009-11-13 Sandhya M. Rao , David A. Turnshek , Daniel. B. Nestor

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 present a detailed study of HI and metals for 110 MgII absorption systems discovered at 1.98 <= z <= 5.33 in the infrared spectra of high redshift QSOs. Using new measurements of rest-frame UV lines from optical spectra of the same…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Michael S. Matejek , Robert A. Simcoe , Kathy L. Cooksey , Eduardo N. Seyffert

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…

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