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Description
We present the first results from a survey of SDSS quasars selected for strong HI damped Ly{alpha} (DLA) absorption with corresponding low equivalent width absorption from strong low-ion transitions (e.g., CII{lambda}1334 and SiII{lambda}1260). These metal-poor DLA candidates were selected from the SDSS fifth release quasar spectroscopic database, and comprise a large new sample for probing low-metallicity galaxies. Medium-resolution echellette spectra from the Keck Echellette Spectrograph and Imager spectrograph for an initial sample of 35 systems were obtained to explore the metal-poor tail of the DLA distribution and to investigate the nucleosynthetic patterns at these metallicities. We have estimated saturation corrections for the moderately underresolved spectra, and systems with very narrow Doppler parameters (b<=5km/s) will likely have underestimated abundances. For those systems with Doppler parameters b>5km/s, we have measured low-metallicity DLA gas with [X/H]<-2.4 for at least one of C, O, Si, or Fe. Assuming non-saturated components, we estimate that several DLA systems have [X/H]<-2.8, including five DLA systems with both low equivalent widths and low metallicity in transitions of both CII and OI. All of the measured DLA metallicities, however, exceed or are consistent with a metallicity of at least 1/1000 of solar, regardless of the effects of saturation in our spectra.
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