******************************************************
   PR #   142
   MSH 15-52 is one of the youngest SNRs which show the clearassociation
   with a pulsar. The X-ray and radio observations found theperiodicity
   of 150ms of the pulsar located in this SNR, PSR 1509-58,and indicate
   an estimate of its age to be ~1600yr which is muchsmaller than that of
   MSH 15-52 of ~10^4yr. The Einstein X-RayObservatory has clearly seen
   the X-ray nebula surrounding PSR 1509-58which is probably synchrotron
   radiation powered by the pulsar. The principal scientific goal of the
   ASCA observations is to resolvethe spectra from the central pulsar,
   from the synchrotron nebula andfrom the thermal shell. This may give
   the information for solving theapparent discrepancy between the age of
   the pulsar and that of SNR.
 ******************************************************