Relevance of geomagnetic storms to relativistic electron flux enhancements at geosynchronous orbit

Abstract:

While examining why only some geomagnetic storms accompany relativistic electron flux enhancements, we found evidence that storms are indeed irrelevant to the occurrence of large flux enhancement at geosynchronous orbit. With the analysis of solar wind parameters and >2MeV geosynchronous electron fluxes, we identify the solar wind conditions that are critical for the large flux enhancements. Along with the observations of flux enhancements without a geomagnetic storm, the observations that only the geomagnetic storms that are associated with such characteristic solar wind conditions accompany the flux enhancements indicate that a storm itself is irrelevant to the occurrence of flux enhancements.