An x-ray view of the cores of galaxy groups: Effects of AGN and mergers on the IGM

Using data from XMM-Newton and Chandra, we have studied a number of X-ray luminous galaxy groups in order to investigate the effects of mergers and AGN activity on their properties. We here present results from four disturbed systems with particularly interesting features. These groups provide examples of AGN heating preventing runaway cooling and mixing enriched gas from the dominant elliptical with the surrounding intra-group medium. We also show that under standard assumptions of hydrostatic equilibrium and relaxation, X-ray analysis may underestimate the gravitational mass of disturbed systems.