Energetic Electron Diffusion by Modulated Heating of the Ionosphere

摘要

abstract_textpAiming to assess the effect on the radiation belts due to modulated heating of the ionosphere, this study adopts the test particle simulation to investigate the resonant interaction between energetic electron and the heater-induced monotonic ELF/VLF (extremely low frequency/very low frequency) waves, with wave distribution obtained by DEMETER observations and numerical computation. It is found that while energy diffusion is weak, pitch angle scattering on energetic electrons can be intense at low equatorial pitch angles near the loss cone for both field-aligned monotonic waves generated by high-latitude heater and highly oblique monotonic waves generated by low-latitude heater. Our investigation supports the feasibility of modulated heating of both high-latitude ionosphere and low-latitude ionosphere for controlled precipitation of energetic electron but also suggests that electron diffusion of field-aligned monotonic waves is more effective, as the diffusion rates can be larger for lower energy electron or at higher equatorial pitch angles and do not vary much with the modulated frequency. Finally, the results are compared with the quasi-linear theory. Though the test particle diffusion coefficients are in good agreement with the quasi-linear diffusion coefficients for field-aligned monotonic waves, they are in very limited agreement for highly oblique monotonic waves, which bring into question the applicability of quasi-linear theory to monotonic highly oblique wave./p/abstract_text