Kinetic Effects on MHD Phenomena in the Magnetosphere

本研究涉及磁层中磁流体动力学（MHD）现象的理论和数据分析。 当磁流体动力学活动受到粒子动力学效应如有限回旋半径效应、俘获粒子效应和波粒共振效应的强烈影响时，传统的磁流体动力学方法就失效了。 本研究中采用的动力学MHD方法将为理解动力学效应对MHD现象，如Pc 4-5磁脉动和磁层亚暴的影响提供理论和观测基础。 从粒子数据计算等离子体不稳定性参数的公式将从这项调查中获得。 通过将理论计算与从空间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。 如果理论上的动力学MHD稳定性分析得到验证，人们可以执行一个实时的数值稳定性分析的基础上，在现场卫星粒子和磁场数据和现实的磁层平衡。 这样的演习可能会导致对暴力MHD活动和相关高能粒子通量的提前警告，这些活动和高能粒子通量会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.