Dynamics of equilibrium upset and electromagnetic energy transformation in the geomagnetotail: A theory and simulation using particles. 2. Numerical simulation using particles

Abstract

The process of rapid geomagnetotail reconfiguration after the equilibrium upset (substorm activation) has been studied using the numerical simulation. The decisive reconfiguration feature consists in the spontaneous formation of nonlinear kinetic small-scale structures in the position of the initial current sheet (CS). Substantially different reconfiguration channels are possible depending on the value of the magnetic field component normal to CS: the dominating process can be the formation of a collisionless slow magnetosonic shock or a forced kinetic current sheet (FKCS). The first option is presented in this part of the work. During the late stages, the process is independent of the type of an initial disturbance; the disturbance intensity is spontaneously formed at a certain final level. Far from CS, the disturbance has the form of a rarefaction wave propagating from CS in background plasma. The reconfiguration results in a large-scale transformation of electromagnetic energy into the energy of plasma flows and heat.