Effect of Interplanetary Disturbances and Geomagnetic Activities on Relativistic Electrons at Geosynchronous Orbit

摘要: Using hourly averaged data of > 2 MeV electron fluxes measured with GOES 7/9/10/11 satellites during 1988–2010, this paper investigates statistically conditions solar wind and geomagnetic activities relativistic electrons flux (Fe) enhancements, describes the dependence at geosynchronous orbit (GEO) on local time, magnetic storms. The results are as follows: (1) time GEO is influenced by activities. noon/midnight ratio grows increasing velocity (Vsw). On Dst index above −50 nT, show regular variation while storms Femax ≥ 103 pfu exhibited no such cycle seasonal dependences. For most intense events, begin to increase main phases storms, for weaker tend recovery phases. (3) density shows a good indicator subsequent enhancement decreased its minimum after 0∼1 days maximum density, Nmax, approaching 0∼2 Nmin. (4) Above 90% events occurred high-speed disturbances, which Vswmax 516 km/s, Dstmin 14.1 cm−3, Bzmin 698 nT. (5) all occurrence probability daily Dstmin, about 53%, percent intense, weak being 36%, 64%, respectively, hardly affected intensities During velocity, AE important indicators