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    PR # 32240                                                                   
     We want to compare the X-ray and optical properties of an optical           
     sample of clusters of galaxies.  This sample is unique because it has       
     well-understood selection criteria and uniformly-calculated velocity        
     dispersions.  We propose to obtain complementary X-ray data with            
     ASCA, an observatory ideally suited for the measurement of Lx, Tx,          
     and iron abundances of this sample.  The relationships between the          
     clusters' velocity dispersions and their X-ray properties will enable       
      us to determine whether the gas and galaxies trace the gravitational       
      potential, test theories of formation of the ICM and cD galaxies,          
      and address why ``complete" catalogs of optical and X-ray clusters a       
     re not always identical, which may arise because some otherwise dense       
       systems may be dynamically                                                
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