Plasma sheet disruption by interchange-generated flow intrusions

A three-dimensional particle-in-cell simulation is used to examine the interaction of interchange-generated flow intrusions with the near-Earth plasma sheet. The interchange heads narrow in cross-tail extent as they propagate earthward and dawnward, and the maximum B-z in the head increases to be comparable to the lobe field strength. The interaction of the flow heads with the near-Earth plasma sheet leads to a strong disruption involving localized reconnection on east-west scales of a few ion inertia lengths. This mechanism may explain several key signatures of substorm onset associated with pre-breakup auroral streamers and the disruption of the near-Earth plasma sheet. Citation: Pritchett, P. L., and F. V. Coroniti (2011), Plasma sheet disruption by interchange-generated flow intrusions, Geophys. Res. Lett., 38, L10102, doi:10.1029/2011GL047527.