Determination of the heat flux by Langmuir probes in the divertor of the COMPASS tokamak Project ID: *BAS-23-02 Provider: Czech Academy of Sciences Period: Jan 01, 2023 - Dec 31, 2024 Principal Investigator: Dr. Miglena Dimitrova Co-investigators R. Dejarnac, D. Tskhakaya, J. Cavalier, K. Bogár, J. Hromasová, M. Tomeš, J. Čaloud Aims of the project: Determining the plasma parameters under various conditions is important in achieving a better understanding of the physical phenomena occurring in a tokamak divertor. Langmuir-probes-based diagnostic is among the most commonly used in tokamaks to measure local parameters. A vast database of data thus obtained has been acquired by the divertor probes of COMPASS tokamak over its 10 years of operation in the Czech Republic. The project aims to obtain radial profiles in the divertor and to compare calculated heat fluxes from probe data to values retrieved from other diagnostics thus assisting in calculating the real heat transmission coefficient. One of the first diagnostics to be installed on the future new tokamak COMPASS-U uses Langmuir probes at the first wall. Due to the high heat fluxes expected in a metallic environment, the diagnostic is based on flush-mounted probes embedded in limiters. A focus will be also put on the electronic system ability to provide reliable measurements when the machine starts operating and electronic board for the probes measurements will be produced.