Narrow Spikes Enhanced by Electron Precipitation under the Inner Radiation Belt

The observation of energetic particles trapped in the magnetosphere has made clear that narrow spikes of these particles as observed at L similar to 1.6 are causally generated by the precipitation of particles trapped in the inner radiation belt. Furthermore, the occurrence frequency of these spikes is well correlated with the local time as coincident with the radio power transmitted from a VLF station located in west Australia, NWC. The results suggest that narrow spikes observed at L similar to 1.6 are mainly caused by the radio power from VLF transmitter, NWC located in Australia.