Event

The tight correlation between the stellar mass and gas-phase metallicity of galaxies is a valuable diagnostic of galaxy evolution. The physical processes that determine the mass-metallicity relation include the inflow rate of relatively pristine gas from the intergalactic medium, metal production in stars, and metal ejection via galactic winds. I will present an analysis of this relationship based on extremely high-quality, stacked spectra of ~200,000 star-forming galaxies from SDSS, describe a second relationship between metallicity and star formation rate at fixed stellar mass, and discuss the implications for galaxy evolution. I will also present new, empirical calibrations that can be applied to individual galaxies at low and high redshift, and use these measurements to demonstrate that high-redshift galaxies are more metal-poor than if they followed the local relationship between mass, metallicity, and star formation rate.