Dissipative Processes in the Magnetopause Boundary Layer and Flux Transfer Events Using the Interball Spacecraft

Work on two quite distinct projects was accomplished: a study of flux transfer events and a study of the magnetosheath-polar cusp interface. The study with Oleg Vaisberg of the Space Research Institute in Moscow used only Interball data. We analyzed the magnetometer data and to assist the observations of Flux Transfer Events (FTEs) to aid in the interpretation of the data. One of the issues was to distinguish between simple traversals of the magnetopause and encounters with FTES. Once that distinction became clear then we could examine the changes in the plasma associated with the FTE. The second study was undertaken to study the turbulent interaction of the magnetosheath flow past the polar cusp. In this study Polar Data was used inside the magnetosphere as Interball crossed through the cusp into the magnetosheath. Our most interesting but least turbulent example was on May 29, 1996 when the interplanetary magnetic field (IMF) was northward. During these conditions the magnetosheath interface with the cusp becomes streamlined due to reconnection above the polar cusp. This reconnection provides a smooth surface across which the velocity shear occurs, thus minimizing turbulence in the interaction. The magnetopause current lies closer to the Earth than the flow boundary. This current layer reverses the field direction from nortward to southward in the neighborhood of the distant cusp and is somewhat noisty but not as much as this region becomes when the IMF is southward.