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DOE OSTI · 1958236

Minimizing separatrix crossings through isoprominence

Burby, J. W. (ORCID:0000000317727647)·Duignan, N. (ORCID:0000000294336490)·Meiss, J. D. (ORCID:0000000200190356)
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Abstract

Abstract A simple property of magnetic fields that minimizes bouncing to passing type transitions of guiding center orbits is defined and discussed. This property, called isoprominence, is explored through the framework of a near-axis expansion. It is shown that isoprominent magnetic fields for a toroidal configuration exist to all orders in a formal expansion about a magnetic axis. Some key geometric features of these fields are described.

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confinement70 PLASMA PHYSICS AND FUSION TECHNOLOGYbouncing, type-transitionsguiding centernear-axis expansionseparatrix crossing

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Burby, J. W. (ORCID:0000000317727647), Duignan, N. (ORCID:0000000294336490), Meiss, J. D. (ORCID:0000000200190356). 2023-02-22. Minimizing separatrix crossings through isoprominence. https://doi.org/10.1088/1361-6587%2Facb968

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