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We present initial results from a Magellan telescope program to image galaxies that give rise to damped Lyman absorbers (DLAs) at 1.63 < z_DLA < 2.37. Our program differs from previous efforts in that we target quasars with intervening Lyman limit systems (LLS) along the line of sight at redshift z_LLS > 3.5. The higher-redshift LLS is applied as a blocking filter to remove the glare of the background quasar at the rest-frame ultraviolet wavelengths of the foreground galaxy. The complete absence of quasar light offers an unimpeded view along the sightline to the redshift of the LLS, allowing an exhaustive search for the DLA galaxy to the sensitivity limit of the imaging data (at or better than 0.25L*). In both of our pilot fields (PKS2000-330, z_DLA=2.033 and SDSS0322-0558, z_DLA=1.69), we identify an L* galaxy within 5 of the sightline which has optical colors consistent with star-forming galaxies at z~2. We examine the correlation between absorption-line properties and galaxy luminosity and impact distance, and compare the high-redshift galaxy and absorber pairs with those known at z<1.
We present the results of a numerical study of a galactic wind model and its implications on the properties of damped Lyman-alpha absorbers (DLAs) using cosmological hydrodynamic simulations. We vary both the wind strength and the internal parameters
We report Hubble Space Telescope Cosmic Origins Spectrograph far-ultraviolet and Arecibo Telescope H{sc i} 21cm spectroscopic studies of six damped and sub-damped Lyman-$alpha$ absorbers (DLAs and sub-DLAs, respectively) at $z lesssim 0.1$, that have
We have obtained high signal:to:noise optical spectroscopy at 5AA resolution of 27 quasars from the APM z$>$4 quasar survey. The spectra have been analyzed to create new samples of high redshift Lyman-limit and damped Lyman-$alpha$ absorbers. These d
The kinematics of damped Lyman alpha absorbers (DLAs) are difficult to reproduce in hierarchical galaxy formation models, particularly the preponderance of wide systems. We investigate DLA kinematics at z=3 using high-resolution cosmological hydrodyn
We have used the SEST 15-metre and Onsala 20-metre telescopes to perform deep (r.m.s. >~ 30 mJy) integrations of various molecular rotational transitions towards damped Lyman-alpha absorption systems (DLAs) known to occult millimetre-loud quasars. We