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   61081
   Superbubble is an important object connecting from individual objects
   (eg. supernovae and OB stars) to galaxy class. However, even energy
   source of the superbubble is still unknown since few observations have
   been made from HEAO-1 A2/LED. Then, we observe the Orion-Eridanus
   superbubble in order to specify the energy source of the superbubble by
   determing its metal abundance. The Orion-Eridanus superbubble is the
   most suitable object for our purpose because it is the nearest, hottest
   and free from background contamination from the galactic plane. Also,
   we discuss the X-ray nature of superbubble as a candicate origine of
   the galactic ridge emission.
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