Finding low-mass groups to extend the cluster scaling relations

Galaxy groups are ideal systems to study baryon physics, which is important forboth using clusters for precision cosmology and understanding galaxy formationand evolution. Over the last decade, our understanding on the ICM properties ofgalaxy groups has been greatly improved. However, we still know little aboutlowmass groups with M_{500}<10^13 h^1 M_sun (or kT < 0.7 keV). Such lowmassgroups are the lightest massive halos that can still hold significant amount ofbaryons. They are the ideal systems to examine the departures of scalingrelations from a simple power law that are expected in simulations. This XMMproposal is a first step to select lowmass groups with M_{500}3 10 x 10^12h^1 M_sun and the requested data are sufficient for some scaling relations. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]