Flux transfer events: Motion and signatures

We present results from a 2.5 dimensional hybrid code simulation for the evolution of flux transfer events (FTEs) during intervals of due southward interplanetary magnetic field (IMF) orientation. The structures invariably form between pairs of reconnection lines, often remaining nearly stationary on the subsolar magnetopause before their motion begins. Although a few structures move sunward, ultimately coalescing with others, most eventually accelerate antisunward, reaching velocities many times greater than the sound speed in the magnetosheath but only about one Alfvén speed greater than the ambient magnetosheath flow. At these velocities, slow mode wakes (but not shocks) marked by density enhancements and magnetic field strength decreases extend outward from the structures into the magnetosheath. Upon encountering the cusps, the structures decelerate, undergo reconnection, and are destroyed.

► Describes results from 2.5D hybrid code simulation for FTE motion and acceleration.
► Compares results with those from state-of-the art analytical models.
► Describes corresponding slow mode perturbations generated in magnetosheath.
► Perturbations appear as events approach Alfvenic Mach number.
► Perturbations are slow mode waves, not shock.