Ion Behaviors in the Reconnection Diffusion Region of a Corrugated Magnetotail Current Sheet

Abstract

The current sheet structure and ion behaviors in a magnetotail reconnection diffusion region are investigated. The multispacecraft analysis suggests a corrugated current sheet structure, interpreted as due to a flapping motion that propagates along geocentric solar magnetospheric along the +y direction in the Geocentric Solar Magnetospheric (GSM) coordinate. The electric field (E) and ion distributions have similarities with those in a planar current sheet. Energetic ions move along the current direction, suggesting the acceleration by the observed reconnection E during the meandering motion. Counterstreaming ions along the current sheet normal suggest the acceleration by the Hall E that is observed to be the dominant component. However, at certain locations, E and counterstreaming ions significantly deviate from the local normal direction, and more than one pair of counterstreaming populations exist, possibly because the corrugated current sheet enables ions entering the current sheet at different locations with different velocities to mix together.