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This work describes the real-time application of the Thomson scattering diagnostics. The upgraded data acquisition system of the Globus-M2 spherical tokamak provides real-time data processing with the delay <2.4 ms for 128 scattering signals from 11 spatial points. The achieved processing performance meets the requirements for Thomson scattering diagnostics of modern thermonuclear facilities and ITER in particular. The paper demonstrates the possibility of plasma electron density control, using Thomson scattering data in the feedback loop. [ABSTRACT FROM AUTHOR]

diagnostics of the plasma electron component by the metho d of Thomson scattering Te(R, t) of laser radiation makes it possible to reliably measure the spatial distributions of the electron temperature and density. One of the obstacles to the implementation of TS diagnostics in thermonuclear reactors is the distortion of the spectral characteristics of the optical system due to radiation-induced absorption and contamination of optical elements with erosion products of the first wall. As a consequence, the reliability of measurements by the TS method will decrease over time. The paper describes the method of multi-laser Thomson scattering, which will solve this problem. The results of the first experiments on the Globus-M2 tokamak are also presented. [ABSTRACT FROM AUTHOR]

Data on plasma disruption processes in the modernized Globus-M2 spherical tokamak are presented. Electron temperature and density profiles before the disruption, immediately after thermal quench and in the stage of plasma current quench are measured using the diagnostics of Thomson scattering of laser radiation. The dependence of the plasma current decay time during disruption on the pre-disruption current value is determined. The distribution of the toroidal current, which is induced during disruption, in the shell of the vessel is determined on the basis of magnetic measurements. Electromagnetic loads on the vessel are calculated. [ABSTRACT FROM AUTHOR]

The diagnostic complex of the Globus-M2 spherical tokamak (R = 36 cm, a = 24 cm), the only operating tokamak in Russia with a divertor plasma configuration, which operates in the range of subthermonuclear temperatures (Te to 1.6 keV, Ti to 4.5 keV) and densities (ne to 2 × 1020 m–3), is described. The Globus‑M2 tokamak is the unique scientific facility, which is a part of the Federal Center for Collective Use of the Ioffe Institute, Russian Academy of Sciences "Materials Science and Diagnostics in Advanced Technologies." This allows third parties to perform their research using it. The work contains a list of all diagnostics currently available on the tokamak. The description of the diagnostics is structured in such a way that the reader gets an idea of their capabilities for measuring plasma parameters with an emphasis on the limits and accuracy of the measured values, and also spatial and time resolution. At the same time, many technical details are omitted in order to save space; references are given to papers with a more detailed description of individual diagnostics. [ABSTRACT FROM AUTHOR]