Keck LGSAO Imaging and Spectroscopy of Massive Passively Evolving Galaxies at z 2.5

We describe deep Keck II laser-guide-star adaptive-optics (LGSAO) imaging of passive galaxies found in fields of radio sources at z 2.5. Although are sample to date is small, we so far have found no examples of objects similar to local normal spheroidal galaxies. Instead, the massive galaxies we have observed for which we can determine the best morphologies seem either to be dominated by disks of old stars with r_e 2 kpc or to be extremely compact, high-density stellar systems with r_e 500 pc. In all cases, any significant star formation in these galaxies seems to have ceased at least 1 Gyr prior to the epoch of observation and, in some cases, much earlier. Some of the implications these morphologies have for formation mechanisms for these first massive galaxies will be explored briefly. We also will describe our first attempt to carry out LGSAO long-slit spectroscopy with NIRC2 on the most compact and highest-surface-brightness galaxy in our sample. This work has been partially supported by NSF grant AST-0307335.