Space Physics Seminar winter-2016

Configuration of the Magnetotail Current Sheet

My presentation is devoted to the magnetic field configuration and distributions of plasma thermal pressure in the magentotail current sheet. We use THEMIS spacecraft observations of the magnetotail current sheet within the downtail region 35RE>r>9R. We collect statistics of current sheets where the current density amplitude jy (in the GSM system) can be estimated owing to measurements of the flapping velocity of the current sheet vertical motion. The current sheet thickness LCS is restored using estimates of the current density amplitude and magnetic field measurements. Observed current sheets are very stretched with the typical scale of the inhomogeneity along x-axis much larger than LCS. The direct comparison of the tension force ~jyBz/c (with Bz is the magnetic field component) and the radial gradient of the plasma pressure demonstrates that this gradient cannot balance the magnetotail current sheet. We discuss other possible mechanisms responsible for the balancing of the magnetotail current sheet and compare obtained results with existing current sheet models.