paper

The VLA-COSMOS 3 GHz Large Project: Evolution of specific star formation rates out to

arXiv:2006.13937 · doi:10.3847/1538-4357/aba044

Abstract

We provide a coherent, uniform measurement of the evolution of the logarithmic star formation rate (SFR) - stellar mass () relation, called the main sequence of star-forming galaxies (MS), for galaxies out to . We measure the MS using mean stacks of 3 GHz radio continuum images to derive average SFRs for 200,000 mass-selected galaxies at in the COSMOS field. We describe the MS relation adopting a new model that incorporates a linear relation at low stellar mass (log(/M)10) and a flattening at high stellar mass that becomes more prominent at low redshift (). We find that the SFR density peaks at and at each epoch there is a characteristic stellar mass () that contributes the most to the overall SFR density. This characteristic mass increases with redshift, at least to . We find no significant evidence for variations in the MS relation for galaxies in different environments traced by the galaxy number density at , nor for galaxies in X-ray groups at . We confirm that massive bulge-dominated galaxies have lower SFRs than disk-dominated galaxies at a fixed stellar mass at . As a consequence, the increase in bulge-dominated galaxies in the local star-forming population leads to a flattening of the MS at high stellar masses. This indicates that "mass-quenching" is linked with changes in the morphological composition of galaxies at a fixed stellar mass.

arXiv comment48 pages (main paper 25 pages, 15 figures). Accepted for publication in The Astrophysical Journal

References in corpus (212)

Cited by in corpus (89)