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arXiv · 2603.20982

A special exact class of three-dimensional equilibria of a magnetized plasma exhibiting closed and nested toroidal magnetic surfaces

D. A. Kaltsas·A. I. Kuiroukidis·G. N. Throumoulopoulos
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Abstract

We construct a special class of three-dimensional (3D) equilibria with pressure anisotropy which showcase closed, nested toroidal magnetic surfaces that are strongly asymmetric in the toroidal direction by applying a sinusoidal perturbation to the axisymmetric Solov'ev equilibrium. They also exhibit distinct closed and nested current-density surfaces. For certain values of the free parameters involved, the perturbations lead to the formation of magnetic islands and stochastic areas in the outer plasma region, while well-defined magnetic surfaces persist in the inner region. In addition, it is demonstrated that the existence of closed and nested surfaces within the plasma region on which the magnetic field modulus is uniform (isomagnetic surfaces) is neither necessary nor sufficient for the existence of respective closed and nested magnetic surfaces.

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D. A. Kaltsas, A. I. Kuiroukidis, G. N. Throumoulopoulos. 2026-03-22. A special exact class of three-dimensional equilibria of a magnetized plasma exhibiting closed and nested toroidal magnetic surfaces. https://arxiv.org/abs/2603.20982

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