The baryon cycle and its (lack of) environmental dependencies

The cycle of gas into and out of galaxies, fueling the conversion of gas into stars, is fundamental to the evolution of galaxies. Indeed, the paradigm that this baryon cycle is self-regulated has proven to be successful at explaining a number of trends, foremost amongst which is the main sequence of star forming galaxies (MS). Combined with a halo mass dependence of the inflow rate and environmental quenching of satellite galaxies, this paradigm represents a compellingly simple picture of galaxy evolution.

We use the current SFRs of morphologically selected samples of disk galaxies drawn from the GAMA survey to test this paradigm in the local universe (z<0.13). We find support for the paradigm of gradually evolving self-regulated balance in the baryon cycle of galaxies in the SFR - M* relation of non-group disk galaxies, which we demonstrate evolves smoothly even over a redshift baseline of dz=0.1. Surprisingly, however, the SFR - M* of non-grouped and group central disk galaxies coincide, evidencing a lack of halo mass dependence even on the mass scale of group halos, and leading to a degree of tension with the picture of a simple self-regulated balance for group central galaxies. This lack of environmental dependence is only exacerbated by the fact that the gas-fueling of the majority of disk dominated satellite group galaxies is nigh identical to that of their group central and non-grouped counterparts, high-lighting a pronounced lack of dependence of the baryon-cycle on the environment and on halo mass in particular.

Finally, we empirically quantify the group-wide impact of an AGN in the group central galaxy on the star-formation of galaxies in galaxy groups as a new and potentially significant environmental influence.