CONCEPTUAL DESIGN OF THE THOMSON SCATTERING DIAGNOSTICS FOR THE KTM TOKAMAK

The article is devoted to the development of a conceptual design for Thomson scattering diagnostics (TSD) for the KTM tokamak, intended for conducting experimental studies, measuring the dynamics of temperature profiles and the electron concentration of high-temperature plasma. The work shows an extensive literature review of TSD implemented on similar installations. Schemes for plasma probing and collection of scattered laser radiation of TSD are presented. Based on an analysis of the structural features of the KTM tokamak and existing technical constraints, the choice of a tangential diagnostic layout in the equatorial plane has been justified as the most reliable and practically feasible option. Key technical requirements for the Thomson scattering diagnostic system have been defined: an electron temperature measurement range of 50 to 3100 eV, an electron density range of 1·10¹⁹ to 2.5·10²⁰ m⁻³, and coverage of at least 10 spatial observation points. Various diagnostic configurations, including vertical viewing schemes, were analyzed, and their implementation on KTM was shown to be infeasible due to a number of engineering and physical limitations. The proposed configuration ensures alignment stability, protection against parasitic radiation, and high spatial resolution. This work represents a well-substantiated design of a Thomson scattering diagnostic system, the implementation of which will significantly enhance the diagnostic capabilities of the KTM tokamak for plasma and material research under controlled thermonuclear fusion conditions.

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