Relativistic electron flux enhancement at synchronous orbit during SEP event on July 14, 2000

Relativistic (E ;1.6 MeV) electron flux enhancements during Solar Energetic Particle (SEP) events as observed by the synchronous FY-2 satellite at orbit located at 105° E are investigated. Energetic protons during SEP events heavily contaminate relativistic electron flux measurements. The ratio of the contamination in the original measurement of relativistic electron flux was over 30% during most of the SEP event on July 14, 2000. A method has been developed to eliminate the contamination caused by the energetic protons, and a “corrected” relativistic electron flux has been obtained. The “cleaned-up” relativistic electron flux measurement shows that relativistic electron flux enhancement at synchronous orbit is well correlated with SEP events during which the IMF Bz has some southward periods. The enhancement could arise as the transport of relativistic electrons from the upstream solar wind into synchronous orbit via the magnetotail.