Ultra‐Low‐Frequency Wave–Particle Interactions in Earth's Outer Radiation Belt

An analytic model of ultra-low-frequency (ULF) waves and test particle simulations are used to investigate -signatures of electron drift resonance observed by the Van Allen Probes during the passage of an interplanetary shock on 31 October 2012, 15:30-16:00 UT. Electron fluxes binned in energy and pitch angle to match the Magnetic Electron Ion Spectrometer (MagEIS) instrument reproduce observed time series, while fluxes binned at higher resolution decay more slowly. The slower rate of decay is because oscillations in particle fluxes produced by ULF waves are phase-mixed across the finite energy width of MagEIS energy channels. Simulations of N = 0 drift resonance and N = -2 drift-bounce resonance are presented to provide insight into ion wave-particle interactions that are a science target of the recently launched Japanese ARASE spacecraft.