Simulation of the outer radiation belt electrons near geosynchronous orbit including both radial diffusion and resonant interaction with Whistler-mode chorus waves

We present the first simulation results for electrons in the outer radiation belt near geosynchronous orbit, where radial diffusion and resonant interactions with whistler-mode chorus outside the plasmasphere are taken into account. Bounce averaged pitch-angle and energy diffusion rates are introduced in the Salammbô code for L ≤ 6.5, for electron energies between 10 keV and 3 MeV and fpe/fce values between 1.5 and 10. Results show that an initial seed population with a power law (Kappa) distribution and a characteristic plasmasheet energy of ∼5 keV can be accelerated up to a few MeV, for 4.5 < L < 6.6 and give a steady state profile similar to the one obtained from average satellite measurements. For a Kp = 4 magnetic storm simulation MeV electron fluxes increase by more than a factor of 10 on a timescale of 1 day. We conclude that whistler-mode chorus waves can be a major electron acceleration process at geostationary orbit.

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