Renormalized theory of the ion cyclotron turbulence in magnetic field--aligned plasma shear flow

TL;DR

This paper develops a renormalized theoretical framework to analyze the nonlinear evolution and saturation of ion cyclotron turbulence in magnetic field--aligned plasma shear flows, accounting for turbulence-shear flow interactions.

Contribution

It introduces a nonlinear dispersion equation that incorporates combined effects of plasma turbulence and shear flow, revealing new mechanisms for ion cyclotron instability saturation.

Findings

Turbulent scattering enhances nonlinear broadening of ion cyclotron resonances.

The theory predicts saturation of ion cyclotron instabilities due to turbulence-shear flow interactions.

Development of nonlinear shear flow driven ion cyclotron instability observed.

Abstract

The analytical treatment of nonlinear evolution of the shear-flow-modified current driven ion cyclotron instability and shear-flow-driven ion cyclotron kinetic instabilities of magnetic field--aligned plasma shear flow is presented. Analysis is performed on the base of the nonlinear dispersion equation, which accounts for a new combined effect of plasma turbulence and shear flow. It consists in turbulent scattering of ions across the shear flow with their convection by shear flow and results in enhanced nonlinear broadening of ion cyclotron resonances. This effect is found to lead to the saturation of ion cyclotron instabilities as well as to the development of nonlinear shear flow driven ion cyclotron instability. 52.35.Ra