Kinetic Effects on MHD Phenomena in the Magnetosphere

本研究涉及与磁层中磁流体动力学（MHD）现象的动力学效应有关的理论和数据分析。当粒子动力学效应（如有限回旋半径效应、捕获粒子效应和波粒共振效应）强烈影响MHD活动时，传统的MHD方法就失效了。本研究中应用的动力学-MHD方法将为理解pc4 -5磁脉动和磁层亚暴等MHD现象的动力学效应提供理论和观测基础。从粒子数据中计算等离子体不稳定性参数的公式将从这项研究中得到。通过将理论计算与天基仪器获得的等离子体稳定性参数进行比较，研究人员将能够研究在空间环境中观测到的等离子体特性与MHD活动之间的关系。如果理论动力学- mhd稳定性分析得到验证，则可以基于原位卫星颗粒和磁场数据以及实际磁层平衡进行实时数值稳定性分析。这样的演习可能导致对剧烈的MHD活动和相关的高能粒子通量的发生发出预警，从而造成不利的空间天气条件。

This investigation deals with theory and data analysis related to kinetic effects on magnetohydrodynamic (MHD) phenomena in the magnetosphere. When MHD activity is strongly affected by particle kinetic effects such as finite gyro-radius effects, trapped particle effects and wave-particle resonance effects, traditional MHD approaches break down. The kinetic-MHD approach to be applied in this study will provide a theoretical and observational basis for understanding kinetic effects on MHD phenomena such as Pc 4-5 magneitic pulsations and magnetospheric substorms. Formulae for computing plasma instability parameters from the particle data will be obtained from this investigation. By comparing theoretical calculations with the plasma stability paramters obtained from space-based instruments, the investigators will be able to study the relationship between observed plasma properties and MHD activity in the space environment. If the theoretical kinetic-MHD stability analysis is verfied, one can perform a real-time numerical stability analysis based on in situ satellite particle and magnetic field data and realistic magnetospheric equilibria. Such an excerise could lead to advanced warning f the onset of violent MHD activity and the associated high energy particle flux that creates adverse space weather conditions.