******************************************************
   PR # 11181
      We propose to observe two distant groups known to be X-ray emitters
    and to make a sensitive search for an intragroup medium in two nearby
    groups containing elliptical galaxies. In the distant groups we will
    be able to measure metallicities of the intragroup medium and to
    determine the gas mass and the total mass in the groups.In the nearby
    groups we expect at least to detect X-ray emission from the elliptic-
    al galaxies and if there is not a detection of the intragroup medium
    we can set very stringent upper limits on the mass of hot gas in the
    nearby groups. Scheduled optical follow up observations will provide
    information on the stellar content of the member galaxies giving us
    the possibility of determining the total baryonic content of the
   groups.
 ******************************************************