Related papers: The SDSS Damped Lya Survey: Data Release 3
We study the incidence rate of damped Ly-a systems associated with the host galaxies of gamma-ray bursts (GRB-host-DLAs) as functions of neutral hydrogen column density (N_HI) and projected star formation rate (SFR) using cosmological SPH…
We establish a robust statistical description of the star-forming galaxy population at the end of cosmic HI reionization ($5.0\le{}z\le6.6$) from a large sample of 52 galaxies with spectroscopically confirmed redshifts from the VIMOS…
We study the evolution with redshift of the number density of Ly$\alpha$ clouds in a CDM model using numerical simulations including photo-ionization and cooling of the baryonic component. The photo-ionizing flux is consistently taken as…
The evolution of the metallicity of damped Lyman alpha systems (DLAs) is investigated in order to understand the nature of these systems. The observational data on chemical abundances of DLAs are analysed with robust statistical methods,…
We present a sample of 45 Damped Lyman-$\alpha$ system (DLA, \nhi\ $ \geq 2 \times 10^{20} {\rm cm}^{-2}$) counterparts (33 detections, 12 upper limits) which host gamma-ray bursts (GRB-DLAs) in order to investigate star-formation and…
We present results from a new Keck spectroscopic survey of UV-faint LBGs in the redshift range 3<z<7. Combined with earlier Keck and published ESO VLT data, our sample contains more than 600 dropouts, offering new insight into the nature of…
(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…
We present the first results of an ongoing program to investigate the kinematic characteristics of high redshift damped lya systems. Because damped lya systems are widely believed to be the progenitors of current massive galaxies, an…
We present the methodology for, and the first results from, a new imaging program aimed at identifying and characterizing the host galaxies of damped Lyman-alpha absorbers (DLAs) at z>2. We target quasar sightlines with multiple…
We have combined the results from our recent observations of Damped and sub-Damped Lyman-alpha systems with the MIKE and UVES spectrographs on the Magellan Clay and VLT Kueyen telescopes with ones from the literature to determine the…
Determining the spatial distribution and intrinsic physical properties of neutral hydrogen on cosmological scales is one of the key goals of next-generation radio surveys. We use the EAGLE galaxy formation simulations to assess the…
We perform joint modeling of the composite rest-frame far-UV (FUV) and optical spectra of redshift 1.85<z<3.49 star-forming galaxies to deduce key properties of the massive stars, ionized ISM, and neutral ISM, with the aim of investigating…
We present elemental abundance measurements for 9 damped Ly-alpha systems (DLAs) and 1 sub-DLA at 0.1 < z < 1.5 from recent observations with the Multiple Mirror Telescope. Most of these absorbers are found to be metal-poor, while 2 are…
Lyman-alpha is now widely used to investigate the galaxy formation and evolution in the high redshift universe. However, without a rigorous understanding of the processes which regulate the Lya escape fraction, physical interpretations of…
We present the HI column density distribution function,\fnh, as measured from dwarf galaxies observed as part of the Faint Irregular Galaxy GMRT (FIGGS) survey. We find that the shape of the dwarf galaxy \fnh\ is significantly different…
The HI 21cm absorption optical depth and the N(HI) derived from Lya absorption can be combined to yield the spin temperature (Ts) of DLAs. Although Ts measurements exist for samples of DLAs with z <0.6 and z >1.7, the intermediate redshift…
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…
Detailed analysis of the spectral lines from two low redshift damped Lyman alpha absorbers (DLA) confirms that they are a heterogeneous population. Both systems have low metal abundances of approximately 0.05 to 0.1 solar. The abundance…
We report results from a programme aimed at investigating the temperature of neutral gas in high-redshift damped Lyman-$\alpha$ absorbers (DLAs). This involved (1) HI 21cm absorption studies of a large DLA sample, (2) VLBI studies to…
At redshifts beyond z>6, as the mean fraction of neutral hydrogen x_HI in the intergalactic medium (IGM) increases, the line flux of Lyman alpha (Lya) emitters can be significantly suppressed, which can result in a decrease in the observed…