Observations of Turbulence and Large Parallel Electric Fields Associated with Magnetic Reconnection in Earth's Magnetotail
Résumé
Magnetic reconnection in the Earth's magnetotail results in release of magnetic flux and plasma towards Earth and away from it. Satellite observations of the Earth's plasma sheet in the Earth's mid-magnetotail show large-amplitude parallel electric field pulses, strong magnetic field turbulence and energized ions and electrons. The turbulent regions often occur near regions of depleted density and bulk flow reversal, and they are associated with magnetic reconnection. The persistent presence of large parallel electric fields in magnetically turbulent plasmas may be indicative of a common dissipative process. We examine turbulent regions in detail with the Magnetospheric Multiscale (MMS) mission to understand the nature of turbulence associated with magnetic reconnection and the path through which ions and electrons are energized. MMS provides four-point, 3-D electric field observations and accurate measurements of the current via the curlometer technique due to spacecraft separations less than electron Debye length. These measurements support a calculation of the energy exchange between fields and particles with unprecedented temporal response and accuracy, which, enables a detailed investigation of turbulent dissipation and acceleration.