Low Masses and High Redshifts: The Evolution of the Mass-Metallicity Relation

by Alaina Henry (NASA Goddard)

Friday 20 Sept 2013, 10:30 → 11:30 Europe/Stockholm

FA31

The mass-metallicity relation in galaxies is sensitive to the exchange of gas between galaxies and the IGM. As such, observations of this correlation constrain the feedback processes that regulate the growth of galaxies. While early studies focusing on relatively massive galaxies (M>10^9-10^9.5 Msun) at z>0.5 have found lower metallicities than are seen locally, constraints on the low mass evolution have been slower to develop. Yet it is at low masses that the effects of star formation feedback are the strongest, and observations have the most leverage to test theoretical models. Emission-line surveys from both ground and space have begun to remedy this shortcoming. I will present new measurements of the mass-metallicity relation in low mass galaxies at both intermediate and high redshifts. With these data, we make new, robust tests for evolution of the mass-metallicity-SFR plane at high redshifts and low masses. Finally, I will show how these observations can be used to test theoretical models where gas inflow, outflow, and star formation form an equilibrium.