CfA OIR Division Lunch Talks
Wednesday, October 3, 2012, 11:00 am, Pratt Conference Room

Probing Gas Halos of Galaxies with SDSS

Guangtun Ben Zhu (Johns Hopkins)

Absorption line spectroscopy provides a powerful tool to explore the distribution and properties of gas surrounding galaxies. I will present the largest sample of metal absorbers ever compiled, obtained from the analysis of 200,000 quasar spectra from SDSS. I will show that the redshift evolution of strong Mg II absorber incidence traces closely the cosmic star formation history. Using galaxies from SDSS as foreground sources and quasars as background sources, I will also present galaxy-gas correlation up to Mpc scale.