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arXiv · 1909.01890

Exact non-symmetric closed line vacuum magnetic fields in a topological torus

Harold Weitzner·Wrick Sengupta
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Abstract

Non-symmetric vacuum magnetic fields with closed magnetic field lines are of interest in the construction of stellarator equilibria. Beyond the result of D.Lortz (ZAMP \textbf{21}, 196 (1970)), few results are available. This work presents a closed-form expression for a class of vacuum magnetic fields in a topological torus with closed field lines. We explicitly obtain the invariants of such a field. We finally show that a three-dimensional low beta magnetohydrodynamic (MHD) equilibrium may be constructed in a topological torus starting with these closed line vacuum magnetic fields.

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Harold Weitzner, Wrick Sengupta. 2019-09-04. Exact non-symmetric closed line vacuum magnetic fields in a topological torus. https://doi.org/10.1063/1.5126688

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