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arXiv · 0906.4414

A self-consistent nonlinear force-free solution for a solar active region magnetic field

M. S. Wheatland·S. Regnier
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Abstract

Nonlinear force-free solutions for the magnetic field in the solar corona constructed using photospheric vector magnetic field boundary data suffer from a basic problem: the observed boundary data are inconsistent with the nonlinear force-free model. Specifically, there are two possible choices of boundary conditions on vertical current provided by the data, and the two choices lead to different force-free solutions. A novel solution to this problem is described. Bayesian probability is used to modify the boundary values on current density, using field-line connectivity information from the two force-free solutions and taking into account uncertainties, so that the boundary data are more consistent with the two nonlinear force-free solutions. This procedure may be iterated until a set of self-consistent boundary data (the solutions for the two choices of boundary conditions are the same) is achieved. The approach is demonstrated to work in application to Hinode/SOT observations of NOAA active region 10953.

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M. S. Wheatland, S. Regnier. 2009-06-24. A self-consistent nonlinear force-free solution for a solar active region magnetic field. https://doi.org/10.1088/0004-637x%2F700%2F2%2Fl88

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