Directly Driven and Unloading Components of Magnetospheric Substorms

9311474赤asofu亚暴研究如果能够确定直接驱动分量和卸载分量，以及它们在亚暴期间如何随时间变化，将具有重要的进展。不幸的是，目前的次暴和风暴指数，如AE、Dst和Ut的精度还不足以满足这种建议；特别是推进了太阳风在磁层中耗散的能量与IMF参数（如V、Bz等）之间关系的研究。本文拟研究：(1)DMSP粒子数据中的“空穴区”是否可以作为极帽开放场线区域的“工作定义”；(2)如果可以，则在多次亚暴期间空穴区大小的变化可以指示开放通量的变化，同时利用DMSP电子数据与IMF Bz、AE、Dst等进行研究。如果开场线区域的“工作定义”可以被证实，那么开场线区域的大小是一个相对简单的几何量，但却是开场线通量和尾叶磁能的度量。通量与IMF和磁层参数的比较有望对亚暴过程提供重要的见解。＊＊＊

9311474 Akasofu Substorm studies would significant by advance if we could identify the directly driven component and the unloading component and how they vary as a function of time during a substorm. Unfortunately, the present accuracy of substorm and storm indices, such as AE, Dst and Ut, is not sufficient for such proposes; in particular in advancing a study of the relationship between the energy dissipated in the magnetosphere with solar wind and IMF parameters, such as V, Bz, , etc. It is proposed to examine: (i) whether "void regions" in DMSP particle data can be regarded as a "working definition" of open field line regions in the polar cap and (ii) if so, changes of the size of the void region during many substorms could indicate changes of the open flux, on the basis of simultaneous DMSP electron data together with the IMF Bz, AE, Dst, , etc. If the "working definition" of the open field line region could be confirmed, the size of the open field line region is a relatively simple geometrical quantity, but yet a measure of the flux of the open field lines and of magnetic energy in the tail lobe. A comparison of the flux with IMF and magnetospheric parameters is expected to provide important insights into substorm processes. ***