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arXiv · 2407.01241

Symmetries of the Electromagnetic Turbulence in a Tokamak Edge

Giovanni Montani·Fabio Moretti
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Abstract

We construct the low-frequency formulation of the turbulence characterizing the plasma in a Tokamak edge. Under rather natural assumptions we demonstrate that, even in the presence of poloidal magnetic fluctuations, it is possible to deal with a reduced model for the turbulence dynamics. This model relies on a single equation for the electric potential, from which all the physical turbulent properties can be calculated. The main result of the present analysis concerns the existence of a specific Fourier branch for the dynamics which demonstrate the attractive character of the two-dimensional turbulence with respect to non-axisymmetric fluctuations. The peculiar nature of this instability, affecting the non-axially symmetric modes, is discussed in some detail, by recovering two different physical regimes.

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Giovanni Montani, Fabio Moretti. 2024-07-01. Symmetries of the Electromagnetic Turbulence in a Tokamak Edge. https://arxiv.org/abs/2407.01241

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