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Information × Registration Number 0215U001173, 0111U010006 , R & D reports Title Interaction of electromagnetic waves and charged particle beams with multicomponent plasma and materials in fusion devices popup.stage_title Head Girka Igor, Registration Date 30-01-2015 Organization Kharkov National University named after V.N. Karazin popup.description2 A new theory of surface cyclotron X-modes (SCXM) in the inhomogeneous magnetoactive plasma is elaborated. Analytical expressions for the eigen frequencies of these modes are found. It is found that their damping rate due to collisions between the particles is greater than the plasma kinetic damping rate. It is found that the presence of a dielectric layer between the metal wall of the chamber and the plasma, which contains in it, does not affect the dispersion properties of SCXM - only the spatial distribution of the tangential component of the SCXM electric field changes. The energy balance equation is derived and analysed for SCXM. Plasma volume of the gas discharge is calculated, that can be sustained by SCXM propagation. It is found that to increase the plasma volume, that is sustained in this discharge, one can increase the value of the external magnetic field, and wavelength as well as to decrease the protective dielectric coating on the inner wall of the metal discharge chamber. Parametric influence of the alternating electric field on the excitation of SCXM is investigated. Taking the Japanese torsatron LHD as an example, it is shown that simultaneous application of two generators, whose operating frequencies are related as natural numbers, allows to manage the instability. A theory of transitional regimes of plasma heating between the regime of minority heating and the regime of mode conversion is elaborated. It is shown how changing the impurity concentration affects the heating regime. Under the transient conditions not only the concentration of impurities determines the channels of electromagnetic waves energy absorption, but in particular the geometry of the location of areas of opacity in the plasma column as well. Thus, for the same concentration of impurity ions both heating regimes can be achieved: that of minority heating and that of mode conversion. Dominant regime of heating is determined by the conditions of interference of electromagnetic waves reflected from different areas of opacity. As a result, energy load to the plasma can be varied within large limits between ion (minority) and electron subsystems. Results of the theory of transitional heating regimes is checked using the full wave numerical simulation code TORIC. The optical properties of compound layers obtained via the implantation of copper ions into the dielectric substrate is experimentally investigated. The method of analysing the spectra of optical transmission and reflection made it possible to determine the composition of compound layers depending on the density of the ion current during the implantation. The dependence of the electronic structure of the dielectric substrate material on the conditions of its receipt, the presence of impurities and irradiation is studied taking as an example the single crystals and ceramics of magnesium aluminum spinel. It is shown that under the thermodynamic equilibrium, growth conditions and doping one can obtain the substrate with low level of anti structure defects. Studying the kinetics of growth and damping of X-ray induced luminescence in these dielectric crystals made it possible to determine that much of the anti structure defects are spatially correlated. This results in a high radiation resistance of spinel crystals and potential to use this material to create compound materials for devices which operate under the conditions of exposure. Product Description popup.authors Гірка І.О. Гірка В.О. Грицина В. Павленко І. popup.nrat_date 2020-04-02 Close