  The study of elemental abundances in Damped Lyman Alpha systems (DLAs) at
high redshift represents one of our best opportunities to probe galaxy
formation and chemical evolution at early times. By coupling measurements made
in high z DLAs with our knowledge of abundances determined locally and with
nucleosynthetic models, we can start to piece together the star formation
histories of these galaxies. Here, we discuss the clues to galactic chemical
evolution that may be gleaned from studying the abundance of Co in DLAs. We
present high resolution echelle spectra of two QSOs, Q2206-199 and Q1223+17,
both already known to exhibit intervening damped systems. These observations
have resulted in the first ever detection of Co at high redshift, associated
with the z= 1.92 DLA in the sightline towards Q2206-199. We find that the
abundance of Co is approximately 1/4 solar and that there is a clear
overabundance relative to iron, [Co/Fe] = +0.31 +/- 0.05. From the abundance of
Zn, we determine that this is a relatively metal-rich DLA, with a metallicity
approximately 1/3 solar. Therefore, this first detection of Co is similar to
the marked overabundance relative to Fe seen in Galactic bulge and thick disk
stars.

Astrophysics