343 research outputs found
Renormalized non-modal theory of the kinetic drift instability of plasma shear flows
The linear and renormalized nonlinear kinetic theory of drift instability of
plasma shear flow across the magnetic field, which has the Kelvin's method of
shearing modes or so-called non-modal approach as its foundation, is developed.
The developed theory proves that the time-dependent effect of the finite ion
Larmor radius is the key effect, which is responsible for the suppression of
drift turbulence in an inhomogeneous electric field. This effect leads to the
non-modal decrease of the frequency and growth rate of the unstable drift
perturbations with time. We find that turbulent scattering of the ion gyrophase
is the dominant effect, which determines extremely rapid suppression of drift
turbulence in shear flow
Renormalized theory of the ion cyclotron turbulence in magnetic field--aligned plasma shear flow
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.RaComment: 21 page
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