A Survey of Small Galaxy Groups at High redshift

The combination of the large sensitivity of the XMM cameras and theavailability of the results of the CNOC2 Survey for Galaxy Groups now offers theunique opportunity to conduct a highly sensitive survey for the Xray propertiesof small Groups at high redshift. With just a single 100ksec exposure, wepropose to acquire data on a few dozen Groups addressing a range of issuesconcerning the physical properties of gas in small Groups. Since a statisticalmass estimate from weak lensing exists for the CNOC2 Groups, we will even beable to address the issue of the gas content as a function of totalgravitational mass. With a single stroke, XMM can extend our knowledge of theevolution of most of the baryonic matter in the Universe out to high redshift. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]