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通过SAMPEX卫星的观测,定量地研究了在CME和CIR磁暴期间1.5～6.0MeV“杀手”电子的通量分布的变化.发现外辐射带的内、外边界都可以被随着L壳指数衰减的函数很好地拟合出来.另外,本文根据这一指数衰减函数和由此得到的动态的外辐射带内、外边界改进了RBC指数的计算,并由此得到CME磁暴有可能比CIR磁暴产生更多的相对论电子.辐射带物理模型STEERB基于三维的Fokker-Planck方程实现,包含局地波粒相互作用、径向扩散和绝热输运等物理过程.由于数值格式的限制,以往的辐射带模型均没有引入局地波粒相互作用相关的交叉扩散项.STEERB模型的对比实验显示,交叉扩散项的忽略能够导致电子通量被高估5倍甚至几个数量级.这个结果说明,交叉扩散项对于辐射带电子通量的准确评估具有重要意义.以往的辐射带物理模型常常采用固定的偶极磁场,忽略了背景磁场变化引起的绝热过程.STEERB模型则采用了时变的背景磁场,同时引入绝热和非绝热过程.对比实验结果显示,绝热输运过程能够显著地影响辐射带电子通量的演化.行星际激波与磁层的相互作用能够在内磁层激发的ULF波;激发的极性模的ULF波会造成“杀手”电子的快速加速过程.极向模和环向模ULF波对漂移-共振加速的作用在不同L值区域有所不同.环向模ULF波对能量电子的加速在L值较大的区域(外磁层)较为重要,而在L值较小的区域(内磁层),极向模ULF波则对能量电子的加速起主要作用.
Through the observation of SAMPEX satellite, the flux distribution of 1.5 ~ 6.0 MeV “killer ” electrons during CME and CIR magnetic storm was quantitatively studied, and the inner and outer boundaries of the outer radiation zone were found to be consistent with L shell index In addition, based on this exponential decay function and the resulting dynamic outer and inner radiative bands, the outer and inner boundaries improve the calculation of the RBC index, and the resulting CME storms are likely to be smaller than the CIR The magnetic storms generate more relativistic electrons. The physical model of the radiative zone, STEERB, is based on the three-dimensional Fokker-Planck equation and involves physical processes such as local wave-particle interactions, radial diffusion and adiabatic transport. Due to the numerical format limitations, The band model does not introduce cross-diffusion terms related to the local wave-particle interactions. A comparative experiment with the STEERB model shows that neglect of cross-diffusion terms can lead to an overstatement of the electron flux by a factor of five or even a few orders of magnitude.This result shows that cross-diffusion Term for the accurate assessment of the radiant flux electronic flux is of great significance.In the past the physical model of the radiation band often uses a fixed dipole magnetic field, ignoring the background caused by magnetic field changes Thermal process. The STEERB model uses a time-varying background magnetic field and introduces both adiabatic and non-adiabatic processes. Comparative experimental results show that the adiabatic transport process can significantly affect the evolution of the electron flux in the radiative band. Of ULF waves excited by the inner magnetosphere and ULF waves of excited polar modes can cause a rapid acceleration of the “killer” electrons. The effect of polarization mode and circular mode ULF waves on drift-resonance acceleration Which is different in different values of L. The ULF wave of the toroidal mode is more important for accelerating the energy electron in the region with larger L value (outer magnetic layer), while in the region with smaller L value (inner magnetic layer), the polar The mode ULF wave plays a major role in the acceleration of energy electrons.