Multi-point observation of the high-speed flows in the plasma sheet

Abstract

The structure of the high-speed flows in the midtail plasma sheet is discussed based on results from multi-point observation of Cluster spacecraft in summer 2001 and 2002. The average rate of change in flow speed along the “dawn–dusk” direction (perpendicular to the main flow and in the plane of the tail current sheet) and along the “north–south” direction suggests that the full width of the flow channel is 12,000–17,000 km in the “dawn–dusk” direction and about 9000–12,000 km in the “north–south” direction. This is consistent with the results obtained from the analysis of the dipolarization front of the flows. The profile of the gradient of the flow in the north–south direction and the shape of the dipolarization front suggest that the BBF has the shape of a localized flux tube.