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   81851
   Many clusters exist in the central region of the Shapley supercluster.
   Since the distances among these clusters are less than 3 Mpc in this
   region, it is likely that the clusters interaction already occurs. The
   gravitational potential could be very large at the center of the
   supercluster. Therefore it means that clusters collision with the most
   highest colliding velocity occurs.  We propose here the observation of
   the linking region between A3558 and A3556 clusters. We may be able to
   observe the shock heatingdue to the cluster-cluster collision which the
   large amount of the mass of the superclusters scale take part in.
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