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arXiv · 1709.02659

Exact Vlasov-Maxwell equilibria for asymmetric current sheets

O. Allanson·F. Wilson·T. Neukirch·Y. -H. Liu·J. D. B. Hodgson
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Abstract

The NASA Magnetospheric Multiscale mission has made in situ diffusion region and kinetic-scale resolution measurements of asymmetric magnetic reconnection for the first time, in the Earth's magnetopause. The principal theoretical tool currently used to model collisionless asymmetric reconnection is particle-in-cell simulations. Many particle-in-cell simulations of asymmetric collisionless reconnection start from an asymmetric Harris-type magnetic field but with distribution functions that are not exact equilibrium solutions of the Vlasov equation. We present new and exact equilibrium solutions of the Vlasov-Maxwell system that are self-consistent with one-dimensional asymmetric current sheets, with an asymmetric Harris-type magnetic field profile, plus a constant nonzero guide field. The distribution functions can be represented as a combination of four shifted Maxwellian distribution functions. This equilibrium describes a magnetic field configuration with more freedom than the previously known exact solution and has different bulk flow properties.

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O. Allanson, F. Wilson, T. Neukirch, Y. -H. Liu, J. D. B. Hodgson. 2017-09-08. Exact Vlasov-Maxwell equilibria for asymmetric current sheets. https://doi.org/10.1002/2017gl074168

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