Simultaneous Influence of Whistler-Mode Chorus and EMIC Waves on Electron Loss in the Earth’s Radiation Belt

Whistler-mode chorus and electromagnetic ion cyclotron waves have long been considered major causes of electron flux changes in the Earth’s outer radiation belt. Here, we report an ideal observation event from two identical satellites, during which the electron flux significantly decreases, followed by a partial recovery under the simultaneous existence of both waves at the same location. The electron flux changes are mostly consistent with predictions from scattering by both waves. We suggest that the combined scattering effect of these two types of waves can be addressed more accurately by a full test particle simulation rather than the current prevailing quasilinear resonant diffusion approach.