Using AO to Identify Damped Lyman α Absorption Systems at Redshift z ~ 2.

We present near-IR AO imaging of two QSOs, each of which lies behind an unidentified damped Lyman α absorption (DLA) system at redshift $z \sim\ 2$. We find candidate systems lying within 2 arcsec of the QSOs. Preliminary data analysis indicates these systems have brightnesses and physical sizes consistent with disk galaxies at the absorber redshifts, although neither redshift has been spectroscopically confirmed. Each DLA exhibits very strong neutral metal absorption, including neutral carbon which is rarely detected in DLA systems. We suggest that certain DLA absorption signatures, in particular C I and molecular hydrogen, may be used to select DLA systems which are likely to arise from large, disk galaxies. [ABSTRACT FROM AUTHOR]