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arXiv · 0801.4519

Comparing magnetic field extrapolations with measurements of magnetic loops

T. Wiegelmann·A. Lagg·S. K. Solanki·B. Inhester·J. Woch
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Abstract

We compare magnetic field extrapolations from a photospheric magnetogram with the observationally inferred structure of magnetic loops in a newly developed active region. This is the first time that the reconstructed 3D-topology of the magnetic field is available to test the extrapolations. We compare the observations with potential fields, linear force-free fields and non-linear force-free fields. This comparison reveals that a potential field extrapolation is not suitable for a reconstruction of the magnetic field in this young, developing active region. The inclusion of field-line-parallel electric currents, the so called force-free approach, gives much better results. Furthermore, a non-linear force-free computation reproduces the observations better than the linear force-free approximation, although no free parameters are available in the former case.

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T. Wiegelmann, A. Lagg, S. K. Solanki, B. Inhester, J. Woch. 2008-01-29. Comparing magnetic field extrapolations with measurements of magnetic loops. https://doi.org/10.1051/0004-6361:20042421

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