Kinetic intermittency in magnetized plasma turbulence

Bogdan Teaca; Alejandro Bañón Navarro; Daniel Told; Frank Jenko

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arXiv · 1607.03421

Kinetic intermittency in magnetized plasma turbulence

Bogdan Teaca·Alejandro Bañón Navarro·Daniel Told·Frank Jenko

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Abstract

We employ magnetized plasma turbulence, described by a gyrokinetic formalism in an interval ranging from the end of the fluid scales to the electron gyroradius, to introduce the first study of kinetic intermittency, in which nonlinear structures formed directly in the distribution functions are analyzed by accounting for velocity space correlations generated by linear (Landau resonance) and nonlinear phase mixing. Electron structures are found to be strongly intermittent and dominated by linear phase mixing, while nonlinear phase mixing dominates the weakly intermittent ions. This is the first time spatial intermittency and linear phase mixing are shown to be self-consistently linked for the electrons and, as the magnetic field follows the intermittency of the electrons at small scales, explain why magnetic islands are places dominated by Landau damping in steady state turbulence.

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Bogdan Teaca, Alejandro Bañón Navarro, Daniel Told, Frank Jenko. 2016-07-12. Kinetic intermittency in magnetized plasma turbulence. https://arxiv.org/abs/1607.03421

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