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Resolving the 180-degree ambiguity in vector magnetic field measurements: The ‘minimum’ energy solution

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I present a robust algorithm that resolves the 180-deg ambiguity in measurements of the solar vector magnetic field. The technique simultaneously minimizes both the divergence of the magnetic field and the electric current density using a simulated annealing algorithm. This results in the field orientation with approximately minimum free energy. The technique is well-founded physically and is simple to implement.

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Metcalf, T.R. Resolving the 180-degree ambiguity in vector magnetic field measurements: The ‘minimum’ energy solution. Sol Phys 155, 235–242 (1994).

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