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arXiv · 1009.1650

Three-dimensional simulations of the orientation and structure of reconnection X-lines

R. Schreier·M. Swisdak·J. F. Drake·P. A. Cassak
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Abstract

This work employs Hall magnetohydrodynamic (MHD) simulations to study the X-lines formed during the reconnection of magnetic fields with differing strengths and orientations embedded in plasmas of differing densities. Although random initial perturbations trigger the growth of X-lines with many orientations, at late time a few robust X-lines sharing an orientation reasonably consistent with the direction that maximizes the outflow speed, as predicted by Swisdak and Drake [Geophys. Res. Lett., 34, L11106, (2007)], dominate the system. The existence of reconnection in the geometry examined here contradicts the suggestion of Sonnerup [J. Geophys. Res., 79, 1546 (1974)] that reconnection occurs in a plane normal to the equilibrium current. At late time the growth of the X-lines stagnates, leaving them shorter than the simulation domain.

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R. Schreier, M. Swisdak, J. F. Drake, P. A. Cassak. 2010-09-08. Three-dimensional simulations of the orientation and structure of reconnection X-lines. https://doi.org/10.1063/1.3494218

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