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arXiv · 2411.16411

Back to the Figure-8 Stellarator

G. G. Plunk·M. Drevlak·E. Rodriguez·R. Babin·A. Goodman·F. Hindenlang
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Abstract

The first stellarator design was a simple tube of plasma twisted and closed on itself in the form of a figure-8. The line of such devices, however, was quickly ended over concerns related to plasma stability. We revisit the figure-8 concept, re-imagined as a modern optimized stellarator, and find the potential for a high degree of stability, as well as exceptionally simple construction. In particular, the design that we find admits planar coils, and is the first quasi-isodynamic stellarator design to have this property. Our work is made possible by recent theoretical progress in the near-axis theory of quasi-isodynamic stellarators, combined with fundamental progress in the numerical solution of three-dimensional magnetohydrodynamic equilibria that cannot be well represented using traditional cylindrical coordinates.

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G. G. Plunk, M. Drevlak, E. Rodriguez, R. Babin, A. Goodman, F. Hindenlang. 2024-11-25. Back to the Figure-8 Stellarator. https://arxiv.org/abs/2411.16411

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