NOAO >   Observing Info >   Approved Programs >   2005B-0379

# Proposal Information for 2005B-0379

PI: Daniel Nestor, University of Florida, dbn@phyast.pitt.edu
Address: Astronomy Department, 211 Bryant Space Science Center, Gainesville, FL 32611-2055, USA

CoI: Sandhya Rao, University of Pittsburgh
CoI: Dave Turnshek, University of Pittsburgh
CoI: Fred Hamann, University of Florida

Title: Imaging Ultra-Strong Low Redshift \ionMg2 Absorbers

Abstract: Quasar absorption lines provide a mechanism to study structures in the Universe selected via gas cross section at cosmologically- significant distances. Importantly, there is no luminosity bias in this type of selection. The Sloan Digital Sky Survey has allowed for the discovery of a very large number of \ionMg2 absorption systems, including an unprecedented number of the strongest systems. We have catalogued a new regime of ultra-strong'' \ionMg2 absorbers, which correspond to enormous kinematic spreads and large \ionH1 column densities. Because of the previous lack of any known ultra-strong systems, their nature has not yet been observationally explored. Thus, we propose to use WIYN to image ~ 8-10 quasar fields containing ultra-strong \ionMg2 absorbers. Two hour exposures in r^\prime will allow us to detect L\lesssim0.1L^* at z~0.5 and tip-tilt will allow small impact parameters to be accessed in order to identify any absorbing galaxy(s) and uncover the nature of these rare systems. We were previously awarded two nights (2005A-0544) as an initial study. Due to weather, we were only able to make use of 1/2 night. However, we were able to use down-time to become familiar with the use of WTTM and used the time-on-sky to acquire images of three of our targets. Though too small a number for statistical significance, these successful and interesting images (recently presented at IAU199: Probing Galaxies Through Quasar Absorption Lines) demonstrate the value of these observations.

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 NOAO >   Observing Info >   Approved Programs >   2005B-0379