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   PR # 21183
    The double clusters ,in which two galaxies are dominant in xray, are 
    still in the intermediate step of the evolution of the cluster. Some 
    X-ray observations show that the cooling flows are not seen in the   
    double clusters although they are considered to be common phenomena  
    in most clusters of galaxies. This suggests that the cooling flow bec
    omes more significant as the merging processes . However the details 
    of the growth of the cooling flow are poorly understood because of   
    the limited energy range of previous Xray imaging observation.  We   
    propose to observe several merging clusters in order to investigate  
    the early stage of clusters evolution by means of measuring the  surf
    ace brightness and temperature distribution using the wide enrgy  ran
   ge and the spatial resolution 
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