Search for high energy γ-rays from supernova 1987A

On February 24, 1987, a supernova was found in the Large Magellanic Cloud at a Chilean observatory, and was named SN 1987A. The Large Magellanic Cloud is present adjoining this Milky Way, and at the distance of about 150,000 light years from the earth. The explosion of a supernova at a short distance like this may be said to be the event for the first time in modern space observation. Further, the shocking thing was that about 3 hours before the discovery in Chile, the signals of neutrinos which seemed to be due to the explosion were recorded on the proton decay experimental device, Kamiokande, which is installed at 1000 m underground at Kamioka Mine. It is the epoch-making event also for elementary particle physics that the astronomical observation was carried out by using neutrinos. It was shown by this observation the theory that 99% of the energy released by the explosion of a supernova is emitted as neutrinos is correct. Supernova and pulsar, the means of observing superhigh energy gamma ray, the selection of the observation site, international cooperation, the cooperation of research organizations, the construction of the observation base and the results of observation of the upper limit value and gamma ray flare by JANZOS are reported. (K.I.)