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arXiv · 2301.03267

Non-modal kinetic theory of the stability of the compressed-sheared plasma flows generated by the inhomogeneous microscale turbulence in the tokamak edge plasma

V. S. Mikhailenko·V. V. Mikhailenko·Hae June Lee
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Abstract

A nonmodal kinetic theory of the stability of the two-dimensional compressed-sheared mesoscale plasma flows, generated by the radially inhomogeneous electrostatic ion cyclotron parametric microturbulence in the pedestal plasma with a sheared poloidal flow, is developed. This theory reveals that the separate spatially uniform Fourier modes of the electrostatic responses of the ions and of the electrons on the mesoscale convective flows are determined only in the frames of references moved with velocities of the ion and electron convective flows. In the laboratory frame, these modes are observed as the compressed-sheared modes with time dependent wave numbers. The integral equation, which governs the separate Fourier mode of the electrostatic potential of the plasma species responses on the mesoscale convective flows, is derived. In this equation, the effects of the compressing and shearing of the convective flows are revealed as the time dependence of the finite ion Larmor radius effect. The solution of this equation for the kinetic drift instability displays the nonmodal transformation of the potential to the zero frequency cell-like perturbation when time elapsed.

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V. S. Mikhailenko, V. V. Mikhailenko, Hae June Lee. 2023-01-09. Non-modal kinetic theory of the stability of the compressed-sheared plasma flows generated by the inhomogeneous microscale turbulence in the tokamak edge plasma. https://doi.org/10.1063/5.0147238

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