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   PR # 42176
   Rosat has discovered x-ray emission from many groups in a
   serendipitous mode from pointed data (Mulchaey et al 1995). However,
   the "best" Rosat groups (e.g. highest flux objects) are expected from
   the all sky survey (RASS) In this proposal we pick the highest flux
   x-ray selected groups from a cross- correlation of the RASS and a
   optically selected catalog of groups selected from the Zwicky
   catalog. At present there are very few ASCA spectra of groups. ASCA
   observations of these high flux objects should provide the best x-ray
   spectra and allow determination of temperature and abundance profiles
   as well as measurement of the abundance of Fe, O, and Si to allow
   determination of the origin of the x-ray emitting gas, constrain the
   form of the potential and the total mass of these systems.
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