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arXiv · 1611.07859

Why does steady-state magnetic reconnection have a maximum local rate of order 0.1?

Yi-Hsin Liu·M. Hesse·F. Guo·W. Daughton·H. Li·P. A. Cassak·M. A. Shay
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Abstract

Simulations suggest collisionless steady-state magnetic reconnection of Harris-type current sheets proceeds with a rate of order 0.1, independent of dissipation mechanism. We argue this long-standing puzzle is a result of constraints at the magnetohydrodynamic (MHD) scale. We perform a scaling analysis of the reconnection rate as a function of the opening angle made by the upstream magnetic fields, finding a maximum reconnection rate close to 0.2. The predictions compare favorably to particle-in-cell simulations of relativistic electron-positron and non-relativistic electron-proton reconnection. The fact that simulated reconnection rates are close to the predicted maximum suggests reconnection proceeds near the most efficient state allowed at the MHD-scale. The rate near the maximum is relatively insensitive to the opening angle, potentially explaining why reconnection has a similar fast rate in differing models.

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Yi-Hsin Liu, M. Hesse, F. Guo, W. Daughton, H. Li, P. A. Cassak, M. A. Shay. 2016-11-23. Why does steady-state magnetic reconnection have a maximum local rate of order 0.1?. https://doi.org/10.1103/physrevlett.118.085101

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