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Information × Registration Number 0210U000704, 0107U010821 , R & D reports Title Ion cyclotron turbulence of plasma with shear flow popup.stage_title Head Mikhailenko Volodymyr, Registration Date 12-03-2010 Organization Kharkov National University named after V.N. Karazin popup.description2 Subject of the research: ionosphere plasma, ion cyclotron turbulence. The purpose of the research: to determine the role of the shear flows and ion cyclotron turbulence in anomalous heating of ions in ionosphere. This research is devoted to theoretical investigations of the nonlinear evolution and saturation of ion cyclotron turbulence of the magnetic field-aligned shear flows. On the base of the solution of the Vlasov equation for the particles distribution function and Poisson equation in a form of the expansion over the powers of the amplitude of the self-consistent electrostatic potential, the nonlinear equation, which describes the nonlinear evolution of the electrostatic potential in magnetic field-aligned plasma shear flows was obtained. On the base of that equation the kinetic theory of the weak turbulence for magnetic field-aligned plasma shear flows was developed in the approximation of the random phases. The developed theory accounts for all processes of the weak turbulence in plasmas immersed into magnetic field. These are the following: decay and coupling of the waves and induced scattering of waves on bare particles and on the polarization clouds of virtual waves. Because this research is devoted to the ion cyclotron turbulence of the plasma shear flows, not only the general forms of matrix elements, which are responsible for above noted processes were obtained, but also their simplified forms, which corresponds to the parameters of the ion cyclotron turbulence. The developed theory of the weak turbulence is a base for the research of the nonlinear evolution and saturation of different ion cyclotron instabilities of the shear flows of the inhomogeneous plasmas in ionosphere and in laboratory conditions, as well as the processes of the anomalous turbulent heating of the plasma components. The renormalized theory of the nonlinear evolution of the ion cyclotron turbulence of plasma shear flows along the magnetic field was developed. That theory grounded on the nonlinear dispersion equation, which accounted for new combined effectof the plasma turbulence and shear flow. It consists in the joint action of the turbulent scattering of ions across the magnetic field and their convection by shear flow. Analytically it manifested as the effect of the nonlinear broadening of the ion cyclotron resonances. This effect leads to the saturation of the ion cyclotron instabilities, as well as to the development of the nonlinear shear flow driven instabilities. The developed theoties of the weak and strong (renormalized) ion cyclotron turbulence were applied to the research of the nonlinear evolution and saturation kinetic and collisional current driven ion cyclotron instabilities, modified by shear flows shear flow driven kinetic and collisional ion cyclotron instabilities. The linear theory of these instabilities was developed by the authors of this investigation. The saturation levels of these instsabilities which are attained due to the action of all proceses were deremined and their comparative analysis was performed, which determines the levels that corrsonds to the observed levels of the ion cyclotron turbulence. Key words: plasma, ionosphere, plasma shear flows, ion cyclotron waves, ion cyclotron instabilities, ion cyclotron turbulence, instabilities saturation. Product Description popup.authors Михайленко В.В. Михайлено В.С. Степанов К.М. popup.nrat_date 2020-04-02 Close