A finite-element method for computing nonlinear force-free fields

The aim of this paper is to propose a new method for computing nonlinear force-free fields. The method is based on an iterative algorithm and a finite-element discretization. After analysing the error for one step, we display some numerical tests which confirm the performance of the code and reveal the superconvergence of the algorithm. A straightforward and potential application of the method is the reconstruction of the coronal magnetic field on the sun from measurements.

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