Adaptive optics imaging of low-redshift damped Lyα quasar absorbers

We have carried out a high angular resolution near-infrared imaging study of the fields of six quasars with seven strong absorption-line systems at z < 0.5, using the Hokupa'a adaptive optics system and the Quick Infrared Camera on the Gemini North telescope. These absorption systems include four classical damped Ly alpha absorbers (DLAs), two sub-DLAs, and one Lyman limit system. Images were obtained in the H or K' filters with FWHM between 0.2 and 0.5 with the goal of detecting the absorbing galaxies and identifying their morphologies. Features are seen at projected separations of 0.5-16.0 from the quasars, and all the fields show features at less than 2 separation. We find candidate absorbers in all seven systems. With the assumption that some of these are associated with the absorbers, the absorbers are low-luminosity <= 0:1L*(H) or L*(K); we do not find any large, bright candidate absorbers in any of our fields. Some fields show compact features that are too faint for quantitative morphology but could arise in dwarf galaxies.