【摘 要】
：
During 2018 major geomagnetic storm,relativistic electron enhancements in extremely low L-shell regions(reaching L～3)have been reported based on observations of ZH-1 and Van Allen probes satellites,and the storm is highly likely to be accelerated by stron
【机 构】
：
National Institute of Natural Hazards,MEMC,Beijing 100085,China;Department of Space Physics,School o
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During 2018 major geomagnetic storm,relativistic electron enhancements in extremely low L-shell regions(reaching L～3)have been reported based on observations of ZH-1 and Van Allen probes satellites,and the storm is highly likely to be accelerated by strong whistler-mode waves occurring near very low L-shell regions where the plasmapause was suppressed.It is very interesting to observe the intense chorus-accelerated electrons locating in such low L-shells and filling into the slot region.In this paper,we further perform numerical simulation by solving the two-dimensional Fokker-Planck equation based on the bounce-averaged diffusion rates.Numerical results demonstrate the evolution processes of the chorus-driven electron flux and confirm the flux enhancement in low pitch angle ranges(20°-50°)after the wave-particle interaction for tens of hours.The simulation result is consistent with the observation of potential butterfly pitch angle distributions of relativistic electrons from both ZH-1 and Van Allen probes.
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