Energetic Electron Scattering in the Earth’s Inner Radiation Belt and the Slot Region

Abstract:

Wave-particle interactions play an important role in energetic electron dynamics in the Earth’s inner radiation belt and the slot region. In this study, we use the high-resolution wave data from Van Allen Probes to construct the new global models of wave properties (e.g., intensity, wave normal angle) for hiss, lightning generated whistlers, and VLF transmitter waves, which are potentially important for the inner radiation belt and the slot region. These state-of-the-art wave models are used to quantify the role of each type of plasma waves in energetic electron scattering process at various L shells and energies. The comparison between the simulation and the Van Allen Probes observations reveals that lightning generated whistlers efficiently scatter electrons from tens of keV to a few MeV at L < 2.5, VLF transmitter waves play a dominant role in scattering electrons at tens of keV at L ~ 2–2.5, thus resulting in the “bifurcated” electron belt, and plasmaspheric hiss accounts for the effective scattering of electrons at higher energies and larger L shells. Our results demonstrate a significant advance in understanding the electron scattering process due to various plasma waves in the inner belt and the slot region.