Effect of the environment on star formation activity and stellar mass for star-forming galaxies in the COSMOS field

TL;DR

This study examines how different environments influence star formation and stellar mass in galaxies, finding that environment has little effect on the galaxy main sequence and star formation rates across cosmic time.

Contribution

It provides a comparative analysis of star-forming galaxies' properties across various environments using radio data, highlighting the minimal environmental impact on the galaxy main sequence.

Findings

Star formation rate declines with cosmic time.

The slope of the galaxy main sequence is shallower than previous consensus.

Environment does not significantly affect the main sequence or star formation trends.

Abstract

We investigate the relationship between environment and the galaxy main sequence (the relationship between stellar mass and star formation rate) and also the relationship between environment and radio luminosity (P$_{\rm 1.4GHz}$) to shed new light on the effects of the environments on galaxies. We use the VLA-COSMOS 3 GHz catalogue that consists of star-forming galaxies (SFGs) and quiescent galaxies (AGN) in three different environments (field, filament, cluster) and for three different galaxy types (satellite, central, isolated). We perform for the first time a comparative analysis of the distribution of SFGs with respect to the main sequence (MS) consensus region from the literature, taking into account galaxy environment and using radio observations at 0.1 $\leq$ z $\leq$ 1.2. Our results corroborate that SFR is declining with cosmic time which is consistent with the literature. We find that the slope of the MS for different $z$ and M$_{*}$ bins is shallower than the MS consensus with a gradual evolution towards higher redshift bins, irrespective of environments. We see no SFR trends on both environments and galaxy type given the large errors. In addition, we note that the environment does not seem to be the cause of the flattening of MS at high stellar masses for our sample.