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arXiv · 1302.5458

A minimally constrained model of self-organized helical states in reversed-field pinches

G. R. Dennis·S. R. Hudson·D. Terranova·P. Franz·R. L. Dewar·M. J. Hole
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Abstract

We show that the self-organized single-helical-axis (SHAx) and double-helical-axis (DAx) states in reversed field pinches can be reproduced in a minimally constrained equilibrium model using only five parameters. This is a significant reduction on previous representations of the SHAx which have required an infinite number of constraints. The DAx state, which has a non-trivial topology, has not been previously reproduced using an equilibrium model that preserves this topological structure. We show that both states are a consequence of transport barrier formation in the plasma core, in agreement with experimental results.

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G. R. Dennis, S. R. Hudson, D. Terranova, P. Franz, R. L. Dewar, M. J. Hole. 2013-06-19. A minimally constrained model of self-organized helical states in reversed-field pinches. https://doi.org/10.1103/physrevlett.111.055003

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