부산대학교 도서관

When the solar events (flare, CME, etc.) occur, many kinds of particles are injected into the Earth’s environment. Especially, solar neutrons produced by the interaction of the accelerated ions with the solar atmosphere are observed by neutron monitors. Sometimes neutron flux increases sharply and decreases in a short time, and it is called ‘GLE (Ground Level Enhancement)’. All of GLEs are related with SPEs (Solar Proton Events). We investigate SPEs accompanying GLE. For about 80% of SPEs accompanying GLE, the fluxes of protons with energies >100 MeV are over 10 pfu. The proton flux in the energy range of >100 has the best correlation with GLE increase rates, compared with proton fluxes in the lower energy range. For about 77% of GLEs, onset time is earlier than onset time of SPEs. In this result, therefore, we can identify the possibility for the prediction of the high-energy proton event ( >100 MeV).