Radial response of radiation belt multi MeV electron enhancements to different solar wind and magnetospheric conditions

We have identified 60 relativistic electron enhancement events at geostationary orbit that occurred between October 2012 and December 2017 by using data from the >2 MeV channel in GOES 13 and 15 satellites. Using data from the Van Allen Probes ECT-REPT instrument, (COMMA) we have compared the occurrence of enhancement events at geostationary orbit with those at different L shells, from L = 2.5 to L = 6.0. Using solar wind data from the OMNI database we have performed a superposed epoch analysis to characterize different parameters associated with those enhancement events by classifying them according to their solar wind driver (CME and CIR), geomagnetic storm intensity as measured by SYM-H index, AE index, and solar wind parameters such as speed, density, pressure and IMF direction. We found that SYM-H index and AE index are particularly efficient at predicting enhancement occurrence closer to Earth, and that enhanced fluxes tend to increase as the indices increase. At the same time, at higher L-shells, relatively low pre-enhancement flux levels play a role in creating a higher "enhancement ratio" for CME storms, even though, statistically, enhanced fluxes are not significantly larger for either type of solar wind driver.