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Information × Registration Number 0224U033375, (0121U109316) , R & D reports Title Investigation of high-frequency generation and heating of plasma, combined discharges and discharges of direct current for treatment of walls of vacuum chambers and advanced methods of diagnostics of plasma and condition of vacuum surfaces. popup.stage_title Дослідження високочастотного створення плазми за допомогою антен різних типів та різного фазування. Адаптація мікрохвильової діагностики на базі ефектів рефракції для стеларатора Ураган-2М. Дослідження різних сценаріїв обробки внутрішніх вакуумних поверхонь.Модернізація існуючих на стелараторі У-2М діагностик і адаптація нових діагностик. Дослідження різних сценаріїв обробки внутрішніх вакуумних поверхонь. Вивчення утримання і нестійкостей плазми У-2М. вивчення ролі швидких частинок в стійкості плазми. Head Moiseenko Volodymyr Ye., Кандидат фізико-математичних наук Registration Date 26-12-2024 Organization National Science Center "Kharkiv Institute of Physics and Technology" popup.description1 The main goal of the work is to develop technology for cleaning vacuum surfaces with plasma of high frequency discharges (HF) of different frequency bands in combination with DC discharge, which will have high efficiency and low level of physical spraying of the installation elements in the vacuum chamber. The aim of the work is also to improve the methods of RF plasma generation. The offered researches are directed on modernization of the existing diagnostics on the U-2M stelarator and adaptation of new diagnostics (such as ECE diagnostics, refractive diagnostics). The dependence of the main parameters of the plasma as well as its stability on the magnetic field, on the experimental conditions in particular on the plasma heating conditions will be investigated. popup.description2 Experiments at the medium stellarator Uragan-2M in Kharkiv, Ukraine, continue as part of the W7-X experimental program. The scenario of obtaining ICRN plasma in the mode of hydrogen addition was experimentally verified on U-2M and qualified on LHD. ICRN discharge studies were conducted in a H2+He mixture with a controlled hydrogen concentration ranging from a few percent to 75%. The dual-strip antenna, simulating the W7-X antenna, operated with monopole phasing. The applied RF power was in the range of ~ 100 kW. A relatively dense plasma up to Ne ~1019 m-3 was created near the first harmonic of the ion cyclotron resonance frequency for hydrogen. The maximum temperature of electrons and ions did not exceed a few tens of eV.The characteristic features of the creation of HF plasma and the propagation of electromagnetic waves in experimental conditions are discussed. Experiments on U-2M and LHD show that the low-impurity scenario of ICRN plasma production is scalable and can be used in large stellarator machines. This is especially important for future experiments on ICRN plasma production in a 1.7 T magnetic field in W-7X.In plasma diagnostic methods based on the refraction of microwave rays, oblique probing of the plasma column is used. They can be used to determine the distribution of plasma density, the distribution of the magnetic field, and the frequency of electron collisions. This technique was tested on a small MAKET device. With the participation of project executors on the JET tokamak, it was shown that confinement in D-T plasma is significantly better than confinement in pure D-plasma, which is due to the presence of fast ions, as well as due to the interaction of TAE modes with turbulence. The influence of ECCD on the TAE mode on the ASDEX-U tokamak was studied. High-frequency AE modes were studied at the ASDEX-U tokamak in the presence of one or a combination of two populations of fast ions. Product Description popup.authors GLAZUNOV Hennadii P. DREVAL Mykola B. KOVTUN Yurii V. KOROVIN Valerii B. KRASIuK Oleksandr Yu. Kulyk Yuliia S. LYSTOPAD Viktor M. MAZNICHENKO Serhii M. MARTSENIUK Yurii P. MOISEENKO Volodymyr Ye. popup.nrat_date 2024-12-26 Close