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arXiv · 0704.0818

Two-scale structure of the electron dissipation region during collisionless magnetic reconnection

M. A. Shay·J. F. Drake·M. Swisdak
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Abstract

Particle in cell (PIC) simulations of collisionless magnetic reconnection are presented that demonstrate that the electron dissipation region develops a distinct two-scale structure along the outflow direction. The length of the electron current layer is found to decrease with decreasing electron mass, approaching the ion inertial length for a proton-electron plasma. A surprise, however, is that the electrons form a high-velocity outflow jet that remains decoupled from the magnetic field and extends large distances downstream from the x-line. The rate of reconnection remains fast in very large systems, independent of boundary conditions and the mass of electrons.

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M. A. Shay, J. F. Drake, M. Swisdak. 2007-04-06. Two-scale structure of the electron dissipation region during collisionless magnetic reconnection. https://doi.org/10.1103/physrevlett.99.155002

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