Nov 29, 2012
Britt Lundgren, UW-Madison
"Revealing the origins and environments of Mg II absorbers with the SDSS and 3D-HST"
Foreground absorption features in the spectra of distant quasars provide largely unbiased probes of the baryon content of galaxies and the intergalactic medium to high redshift. Absorption features from singly-ionized magnesium (Mg II) are particularly prolific in optical spectra within the range 0.3 < z < 2.0, and are expected to trace a wide range of galaxy environments and halo-disk processes, though detecting the individual host galaxies of these absorbers presents an observational challenge. The extraction of ~100,000 quasar absorption line systems from the Sloan Digital Sky Survey -I/II and -III has begun to revolutionize our understanding of the host galaxies and environments of Mg II absorbers. I will present highlights from my work examining the statistical properties of Mg II host galaxies from stacking and clustering measurements using the largest absorption line dataset ever compiled. I will also present new direct observations of Mg II host galaxies at z > 1 from the 3D-HST Survey. These analyses reveal compelling links between high equivalent width Mg II absorbers and large-scale star formation-driven outflows, which I will discuss in the context of other recent findings from the literature.