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arXiv · 2010.11889

On the quasi-three dimensional configuration of magnetic clouds

Qiang Hu·Wen He·Jiong Qiu·A. Vourlidas·Chunming Zhu
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Abstract

We develop an optimization approach to model the magnetic field configuration of magnetic clouds, based on a linear-force free formulation in three dimensions. Such a solution, dubbed the Freidberg solution, is kin to the axi-symmetric Lundquist solution, but with more general "helical symmetry". The merit of our approach is demonstrated via its application to two case studies of in-situ measured magnetic clouds. Both yield results of reduced $\chi^2\approx 1$. Case 1 shows a winding flux rope configuration with one major polarity. Case 2 exhibits a double-helix configuration with two flux bundles winding around each other and rooted on regions of mixed polarities. This study demonstrates the three-dimensional complexity of the magnetic cloud structures.

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Qiang Hu, Wen He, Jiong Qiu, A. Vourlidas, Chunming Zhu. 2020-10-22. On the quasi-three dimensional configuration of magnetic clouds. https://doi.org/10.1029/2020gl090630

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