Examination of radiation belt dynamics during substorm clusters: Activity drivers and dependencies of trapped flux enhancements

Dynamical variations of radiation belt trapped electron fluxes are examined to better understand the variability of enhancements linked to substorm clusters. Analysis is undertaken using the Substorm Onsets and Phases from Indices of the Electrojet (SOPHIE) substorm cluster algorithm for event detection. Observations from Low Earth Orbit (LEO) are complemented by additional measurements from Medium Earth Orbit (MEO) to allow a major expansion in the energy range considered, from medium energy energetic electrons up to ultra-relativistic electrons. The number of substorms identified inside a cluster does not depend strongly on solar wind drivers or geomagnetic indices either before, during, or after the cluster start time. Clusters of substorms linked to moderate (100nT