Unmasking damped Lyα absorbing galaxies at z<1

I review current results from searching for galaxies giving rise to damped Lyα absorbers (DLAs) at z. Using 14 confirmed DLA galaxies, I further show that intermediate-redshift galaxies possess a large H I envelope out to 24-30 h^-1 kpc in radius. The photometric and spectral properties of these galaxies confirm that DLA galaxies are drawn from the typical field population, and not from a separate population of low surface brightness or dwarf galaxies. The spatial distribution of metals in the cold ISM of intermediate-redshift galaxies is characterised by a radial gradient of -0.041± 0.012 dex per kiloparsec (or equivalently a scale length of 10.6 h^-1 kpc) to 30 h^-1 kpc radius based on an ensemble of six galaxy-DLA pairs. Adopting this abundance gradient and known N(H I) profiles of nearby galaxies, I show that the observed low metal content of the DLA population can arise naturally as a combination of gas cross-section selection and metallicity gradients commonly observed in local disk galaxies.