Clues to the Origin of the Mass-Metallicity Relation: Dependence on Star Formation Rate and Galaxy Size
Abstract
We use a sample of 43,690 galaxies selected from the Sloan Digital Sky Survey Data Release 4 to study the systematic effects of specific star formation rate (SSFR) and galaxy size (as measured by the half-light radius, rh) on the mass-metallicity relation. We find that galaxies with high SSFR or large rh for their stellar mass have systematically lower gas-phase metallicities (by up to 0.2 dex) than galaxies with low SSFR or small rh. We discuss possible origins for these dependencies, including galactic winds/outflows, abundance gradients, environment, and star formation rate efficiencies.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 2008
- DOI:
- 10.1086/527296
- arXiv:
- arXiv:0711.4833
- Bibcode:
- 2008ApJ...672L.107E
- Keywords:
-
- galaxies: abundances;
- galaxies: ISM;
- Astrophysics
- E-Print:
- Accepted by ApJ Letters