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arXiv · 2306.08642

Nonlinear equilibria and transport processes in burning plasmas

Matteo Valerio Falessi·Liu Chen·Zhiyong Qiu·Fulvio Zonca
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Abstract

In this work, we put forward a general phase-space transport theory in axisymmetric tokamak plasmas based upon the concept of zonal state (ZS). Within this theoretical framework, the ZS corresponds to a renormalized plasma nonlinear equilibrium consisting of phase-space zonal structures (PSZS) and zonal electromagnetic fields (ZFs) which evolve self-consistently with symmetry breaking fluctuations and sources/collisions. More specifically, our approach involves deriving governing equations for the evolution of particle distribution functions (i.e, PSZS), which can be used to compute the corresponding macro-/meso-scale evolving magnetized plasma equilibrium adopting the Chew Goldberger Low (CGL) description, separating the spatiotemporal microscale structures. The nonlinear physics of ZFs and of geodesic acoustic modes/energetic particle driven geodesic acoustic modes is then analyzed to illustrate the implications of our theory.

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Matteo Valerio Falessi, Liu Chen, Zhiyong Qiu, Fulvio Zonca. 2023-06-14. Nonlinear equilibria and transport processes in burning plasmas. https://arxiv.org/abs/2306.08642

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