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arXiv · 2112.09504

Energetic bounds on gyrokinetic instabilities. Part I: Fundamentals

P. Helander·G. G. Plunk
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Abstract

Upper bounds on the growth of free energy in gyrokinetics are derived. These bounds apply to all local gyrokinetic instabilities in the geometry of a flux tube, i.e. a slender volume of plasma aligned with the magnetic field, regardless of the geometry of field, the number of particle species, or collisions. The results apply both to linear instabilities and to the nonlinear growth of finite-amplitude fluctuations.

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P. Helander, G. G. Plunk. 2021-12-17. Energetic bounds on gyrokinetic instabilities. Part I: Fundamentals. https://doi.org/10.1017/s0022377822000277

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