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arXiv · 1603.06968

Suppression of phase mixing in drift-kinetic plasma turbulence

J. T. Parker·E. G. Highcock·A. A. Schekochihin·P. J. Dellar
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Abstract

Transfer of free energy from large to small velocity-space scales by phase mixing leads to Landau damping in a linear plasma. In a turbulent drift-kinetic plasma, this transfer is statistically nearly canceled by an inverse transfer from small to large velocity-space scales due to "anti-phase-mixing" modes excited by a stochastic form of plasma echo. Fluid moments (density, velocity, temperature) are thus approximately energetically isolated from the higher moments of the distribution function, so phase mixing is ineffective as a dissipation mechanism when the plasma collisionality is small.

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J. T. Parker, E. G. Highcock, A. A. Schekochihin, P. J. Dellar. 2016-03-22. Suppression of phase mixing in drift-kinetic plasma turbulence. https://doi.org/10.1063/1.4958954

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