Growth, Sudden Onset and Current Disruption in Substorms: Role of Reconnection and Ideal Instabilities

点击翻译按钮获取中文摘要

This investigation aims to develop a time-dependent theory of magnetospheric substorms, with correct time scales for the growth phase, the pre-onset interval and the expansion phase. The study will use an analytical model and a two-dimensional, low- dissipation, magnetohydrodynamic (MHD) model developed under a previous award. The model includes the geometrical and dynamical features of current sheets in the early growth phase and the pre- onset interval, and clarifies the role of forced reconnection. The investigation involves the study of the role of collisionless effects, the role of ideal ballooning/kink instabilities in the magnetotail, and the role of ionospheric boundary conditions. Emphasis will be on obtaining the correct time-history and spatial signatures found by observations in the growth and expansion phases of substorms.