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arXiv · 1411.2490

An overview of flux braiding experiments

A. L. Wilmot-Smith
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Abstract

Parker has hypothesised that, in a perfectly ideal environment, complex photospheric motions acting on a continuous magnetic field will result in the formation of tangential discontinuities corresponding to singular currents. We review direct numerical simulations of the problem and find the evidence points to a tendency for thin but finite thickness current layers to form, with thickness exponentially decreasing in time. Given a finite resistivity these layers will eventually become important and cause the dynamical process of energy release. Accordingly, a body of work focusses on evolution under continual boundary driving. The coronal volume evolves into a highly dynamic but statistically steady state where quantities have a temporally and spatially intermittent nature and where the Poynting flux and dissipation are decoupled on short timescales. Although magnetic braiding is found to be a promising coronal heating mechanism much work remains to determine its true viability. Some suggestions for future study are offered.

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A. L. Wilmot-Smith. 2014-11-10. An overview of flux braiding experiments. https://doi.org/10.1098/rsta.2014.0265

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