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 h...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.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.41904149 and 12173038)Stable-Support Scientific Project of China Research Institute of Radiowave Propagation(Grant No.A132001W07)the National Institute of Natural Hazards,Ministry of Emergency Management of China(Grant No.2021-JBKY-11).
文摘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.