Effects of environment on sSFR profiles of late type galaxies in the CALIFA survey

COENDA, VALERIA; MAST, DAMIAN; MARTÍNEZ, JULIÁN; MURIEL, HERNÁN; MERCHÁN, MANUEL

La Serena, Chile

Congreso; Binational AAA-SOCHIAS Meeting; 2018

We analyze the dependence on environment of the radial profiles of sSFR of a sample of late-type galaxies drawn from the CALIFA survey. We consider three different discrete environments: isolated galaxies, galaxies in pairs, and galaxies in groups. We split our galaxy samples into four bins in stellar mass, covering the range 9 ≤ log(M/M⊙) ≤ 12, and compare their sSFR as a function of the radius (in units of their effective radius) throughout the three environments. We find that, as in previous works in the literature, as we move from less to more massive galaxies, profiles of sSFR lower and bend towards the inner regions of the galaxies. Mass primarily determines the sSFR profiles of late type galaxies. Morphology matters: the relative size of the bulge plays a key role in depressing star formation towards the center of late-type galaxies. The influence of AGNs is only secondary to mass. The group environment determines clear differences in the sSFR profiles of galaxies. On the other hand, isolated galaxies and galaxies in pairs do not differ significantly, with the probable exception of log(M/M⊙) ≥ 11. There is evidence of an outside-in action upon galaxies in groups with masses 9 ≤ log(M/M⊙) ≤ 10. There is evidence of a much stronger star formation suppression in the inner regions of massive galaxies in groups, which may be an indication of a different merger history.