Kinetic simulations of 3-D reconnection and magnetotail disruptions

Abstract

The effects of a full 3-D geometry on collisionless reconnection are still basically unknown. Large scale 3-D particle-in-cell simulations are used to investigate the role of internal instabilities associated with the third dimension on the reconnection process and to examine the effect of boundary conditions which are imposed on a localized reconnection region by the large scale system. For an idealized current sheet of the Harris type the internal instabilities are found not to substantially alter the structure of the 2-D diffusion region. A convection electric field localized near midnight drives a magnetotail configuration to reconnect with the formation of a thin, electron dominated current sheet and a region 2 sense field-aligned current system in the reconnection region. These processes, however, do not appear to exhibit the characteristics associated with substorm onset.