Using data from four deep fields ( COSMOS , AEGIS , ECDFS , and CDFN ) , we study the correlation between the position of galaxies in the star formation rate ( SFR ) versus stellar mass plane and local environment at z < 1.1 .
To accurately estimate the galaxy SFR , we use the deepest available Spitzer/MIPS 24 and Herschel/PACS datasets .
We distinguish group environments ( M _ { halo } \sim 10 ^ { 12.5 - 14.2 } M _ { \odot } ) based on the available deep X-ray data and lower halo mass environments based on the local galaxy density .
We confirm that the Main Sequence ( MS ) of star forming galaxies is not a linear relation and there is a flattening towards higher stellar masses ( M _ { * } > 10 ^ { 10.4 - 10.6 } M _ { \odot } ) , across all environments .
At high redshift ( 0.5 < z < 1.1 ) , the MS varies little with environment .
At low redshift ( 0.15 < z < 0.5 ) , group galaxies tend to deviate from the mean MS towards the region of quiescence with respect to isolated galaxies and less-dense environments .
We find that the flattening of the MS toward low SFR is due to an increased fraction of bulge dominated galaxies at high masses .
Instead , the deviation of group galaxies from the MS at low redshift is caused by a large fraction of red disk dominated galaxies which are not present in the lower density environments .
Our results suggest that above a mass threshold ( \sim 10 ^ { 10.4 } -10 ^ { 10.6 } M _ { \odot } ) stellar mass , morphology and environment act together in driving the evolution of the SF activity towards lower level .
The presence of a dominating bulge and the associated quenching processes are already in place beyond z \sim 1 .
The environmental effects appear , instead , at lower redshifts and have a long time-scale .