A survey of galaxies associated with z 3 Damped Lyman Alpha Absorbers: inferring typical absorber mass via galaxy bias

We present results from a systematic survey for Lyman break galaxies (LBGs) associated with damped Lyman alpha absorption systems (DLAs) at z ˜ 3. We use ˜ 500 LBG spectra obtained from 9 quasar fields (10 DLAs) to calibrate a u'BVRI photometric selection technique and to establish the z ˜ 3 LBG-DLA cross-correlation. Since DLAs are thought to be the progenitors of typical present-day galaxies like the Milky Way, understanding the mass and environment of high-z DLAs is necessary for a complete model of galaxy formation. From the LBG-DLA cross-correlation, we determine the DLA bias and hence the mass of typical DLAs within the context of CDM cosmology