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High-Ion Absorption in Seven GRB Host Galaxies at z=2-4: Evidence for both Circumburst Plasma and Outflowing Interstellar Gas
Andrew J. Fox, Cédric Ledoux, Paul M. Vreeswijk +2
(Abridged) We use VLT/UVES high-resolution optical spectroscopy of seven GRB afterglows at z_GRB>2 to investigate circumburst and interstellar plasma in the host galaxies. Our samp…
Early spectroscopic identification of SN 2008D
D. Malesani, J. P. U. Fynbo, J. Hjorth +27
SN 2008D was discovered while following up an unusually bright X-ray transient in the nearby spiral galaxy NGC 2770. We present early optical spectra (obtained 1.75 days after the…
First detection of CO in a high-redshift DLA
R. Srianand, P. Noterdaeme, C. Ledoux +1
We present the first detection of carbon monoxide (CO) in a damped Lyman-alpha system (DLA) at z_abs =2.41837 toward SDSS J143912.04+111740.5. We also detected H_2 and HD molecules…
Molecular hydrogen in high-redshift Damped Lyman-alpha systems: The VLT/UVES database
P. Noterdaeme, C. Ledoux, P. Petitjean +1
We present the current status of ongoing searches for molecular hydrogen in high-redshift (1.8 < zabs <= 4.2) Damped Lyman-alpha systems (DLAs) capitalising on observations perform…
The Nitrogen and Oxygen abundances in the neutral gas at high redshift
Patrick Petitjean, Cedric Ledoux, R. Srianand
We study the Oxygen and Nitrogen abundances in the interstellar medium of high-redshift galaxies. We use high resolution and high signal-to-noise ratio spectra of Damped Lyman-alph…
Multiphase Plasma in Sub-Damped Lyman Alpha Systems: A Hidden Metal Reservoir
Andrew J Fox, Patrick Petitjean, Cédric Ledoux +1
We present a VLT/UVES spectrum of a proximate sub-damped Lyman-alpha (sub-DLA) system at z=2.65618 toward the quasar Q0331-4505 (z_qso=2.6785+/-0.0030). Absorption lines of O I, Si…
The host of GRB 060206: kinematics of a distant galaxy
Christina C. Thoene, Klaas Wiersema, Cedric Ledoux +13
We present early (starting 1.6h after the burst) WHT/ISIS optical spectroscopy of the afterglow of the gamma-ray burst GRB 060206 detecting a range of metal absorption lines and th…
Excitation mechanisms in newly discovered H2-bearing Damped Lyman-alpha clouds: systems with low molecular fractions
P. Noterdaeme, C. Ledoux, P. Petitjean +3
We probe the physical conditions in high-redshift damped Ly-alpha systems using the observed molecular fraction and the rotational excitation of molecular hydrogen. We report two n…
C IV absorption in damped and sub-damped Lyman-alpha systems: correlations with metallicity and implications for galactic winds at z~2-3
Andrew J. Fox, Cédric Ledoux, Patrick Petitjean +1
We present a study of C IV absorption in a sample of 63 damped Lyman-alpha (DLA) systems and 11 sub-DLAs in the redshift range 1.75<z_abs<3.61, using a dataset of high-resolution (…
Intervening Metal Systems in GRB and QSO sight-lines: The Mgii and Civ Question
Vladimir Sudilovsky, Sandra Savaglio, Paul Vreeswijk +3
Prochter et al. 2006 recently found that the number density of strong intervening 0.5<z<2 MgII absorbers detected in gamma-ray burst (GRB) afterglow spectra is nearly 4 times large…
Physical conditions in the neutral interstellar medium at z=2.43 toward Q2348-011
P. Noterdaeme, P. Petitjean, R. Srianand +2
We obtained a high-resolution VLT-UVES spectrum of the quasar Q2348-011 over a wavelength range that covers most of the prominent metal and molecular absorption lines from the log…
Hot Halos around High Redshift Protogalaxies: Observations of O VI and N V Absorption in Damped Lyman Alpha systems
Andrew J. Fox, Patrick Petitjean, Cedric Ledoux +1
(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 I…
The nature of the dwarf starforming galaxy associated with GRB 060218 / SN2006aj
K. Wiersema, S. Savaglio, P. M. Vreeswijk +9
We present high resolution VLT UVES and low resolution FORS optical spectroscopy of supernova 2006aj and its host galaxy, associated with the nearby (z = 0.03342) gamma-ray burst G…
Three intervening galaxy absorbers towards GRB060418: faint and dusty?
Sara L. Ellison, Paul Vreeswijk, Cedric Ledoux +8
We present an analysis of three strong, intervening Mg II absorption systems (z_abs = 0.603, 0.656, 1.107) towards the optical afterglow of gamma-ray burst (GRB) 060418. From high…
Metallicity as a criterion to select H2 bearing Damped Lyman-alpha systems
Patrick Petitjean, C. Ledoux, P. Noterdaeme +1
We characterize the importance of metallicity on the presence of molecular hydrogen in damped Lyman-alpha (DLA) systems. We construct a representative sample of 18 DLA/sub-DLA syst…
Velocity-Metallicity Correlation for high-z DLA Galaxies: Evidence for a Mass-Metallicity Relation?
C. Ledoux, P. Petitjean, J. P. U. Fynbo +2
We used our database of VLT-UVES quasar spectra to build up a sample of 70 Damped Lyman-alpha (DLA) or strong sub-DLA systems with total neutral hydrogen column densities of log N(…
Abundance analysis of 5 early-type stars in the young open cluster IC2391
Ch. Stuetz, S. Bagnulo, E. Jehin +4
It is unclear whether chemically peculiar stars of the upper main sequence represent a class completely distinct from normal A-type stars, or whether there exists a continuous tran…
An optical supernova associated with the X-ray flash XRF 060218
E. Pian, P. A. Mazzali, N. Masetti +42
Long-duration gamma-ray bursts (GRBs) are associated with type Ic supernovae that are more luminous than average and that eject material at very high velocities. Less-luminous supe…
Molecular Hydrogen in a Damped Lyman-alpha System at z_abs=4.224
C. Ledoux, P. Petitjean, R. Srianand
We present the direct detection of molecular hydrogen at the highest redshift known today (z_abs=4.224) in a Damped Lyman-alpha (DLA) system toward the quasar PSS J1443+2724. This…
The most metal-poor damped Ly alpha system at z<3: constraints on early nucleosynthesis
P. Erni, P. Richter, C. Ledoux +1
To constrain the conditions for very early nucleosynthesis in the Universe we compare the chemical enrichment pattern of an extremely metal-poor damped Lyman alpha (DLA) absorber w…
Relative abundance pattern along the profile of high redshift Damped Lyman-alpha systems
E. Rodriguez, P. Petitjean, B. Aracil +2
We investigated abundance ratios along the profiles of six high-redshift Damped Lyman-alpha systems, three of them associated with H2 absorption, and derived optical depths in each…
Early-type stars observed in the ESO UVES Paranal Observatory Project: I -- Interstellar Na I UV, Ti II and Ca II K observations
I. Hunter, J. V. Smoker, F. P. Keenan +5
We present an analysis of interstellar Na I (lambda=3302.37Å, 3302.98Å), Ti II (lambda=3383.76Å) and Ca II K (lambda=3933.66Å) absorption features for 74 sightlines towards O- and…
Kinematics and star formation activity in the z=2.03954 damped Lyman-alpha system towards PKS 0458-020
Janine Heinmueller, Patrick Petitjean, Cedric Ledoux +2
We present UVES observations of the log N(HI)= 21.7 damped Lyman-alpha system at z=2.03954 towards the quasar PKS 0458-020. HI Lyman-alpha emission is detected in the center of the…
A Lyman-alpha blob in the GOODS South field: evidence for cold accretion onto a dark matter halo
Kim Nilsson, Johan P. U. Fynbo, Palle Moller +2
We report on the discovery of a z = 3.16 Lyman-alpha emitting blob in the GOODS South field. The blob has a total Ly-alpha luminosity of ~ 10^(43) erg s^(-1) and a diameter larger…