Ground-Based Observations of Low-Redshift Damped Lyman-Alpha Systems

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Ground based observations of low redshift damped Lyman alpha systemsDavid TurnshekObservations of quasi stellar objects (QSO's) show patterns of absorption lines. These lines originate in the intervening gaseous regions distributed throughout the Universe. They appear as a spectral line due to the Lyman alpha series of hydrogen. The vast majority of these lines are narrow Lyman alpha lines. Occasionally one sees a line that arises from a very dense region. In these cases the line is not quite as narrow. These are the damped Lyman alpha systems.Dr. Turnshek proposes to follow up the known low redshift damped Lyman alpha systems with ground based facilities in order to elucidate various properties of these galaxies: luminosities and separations from the QSO lines of sight, HI cross sections, and number of galaxies per comoving volume; galaxy morphologies, surface brightnesses, colors, stellar populations, and star formation rates; element abundances and dust; and 21 cm spin temperatures and 21 cm metal line kinematics. A wide variety of accepted and planned ground based programs are planned using several ground based telescopes.