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arXiv · 1706.09662

Three-dimensional oscillatory magnetic reconnection

J. O. Thurgood·D. I. Pontin·J. A. McLaughlin
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Abstract

Here we detail the dynamic evolution of localised reconnection regions about three-dimensional (3D) magnetic null points by using numerical simulation. We demonstrate for the first time that reconnection triggered by the localised collapse of a 3D null point due to an external MHD wave involves a self-generated oscillation, whereby the current sheet and outflow jets undergo a reconnection reversal process during which back-pressure formation at the jet heads acts to prise open the collapsed field before overshooting the equilibrium into an opposite-polarity configuration. The discovery that reconnection at fully 3D nulls can proceed naturally in a time-dependent and periodic fashion is suggestive that oscillatory reconnection mechanisms may play a role in explaining periodicity in astrophysical phenomena associated with magnetic reconnection, such as the observed quasi-periodicity of solar and stellar flare emission. Furthermore, we find a consequence of oscillatory reconnection is the generation of a plethora of freely-propagating MHD waves which escape the vicinity of the reconnection region

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J. O. Thurgood, D. I. Pontin, J. A. McLaughlin. 2017-06-29. Three-dimensional oscillatory magnetic reconnection. https://doi.org/10.3847/1538-4357%2Faa79fa

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