Monday

We present results from the XXL and GAMA surveys investigating the evolution of galaxies in groups at different stages of formation. We compare the galaxy properties of optically selected groups with matched aperture X-ray photometry to test whether differences in the X-ray emitting gas are linked to differences in the group age or feedback history.

We find that galaxy groups with high X-ray luminosity contain a lower fraction of blue, star forming galaxies, when compared with low X-ray luminosity groups. The X-ray bright groups also have a more dominant, passive central galaxy, than seen in low X-ray luminosity groups. These results demonstrate that our group samples can separated by group formation time, allowing a comparison of environmental quenching mechanisms at different epochs.