The first measurements of edge plasma electron temperature by the Thomson scattering method on a TUMAN-3M tokamak

The results of the first measurements of the electron temperature in edge plasma of the TUMAN-3M tokamak are presented. These results were obtained with recently installed Thomson scattering diagnostics system. The experiments were performed in 2023 year with test light collecting system set up for observation of plasma in region with $r/a >$ 0.75 including $r/a$ = 0.95 edge point. The main objective of measurements in this plasma region was to determine sensitivity of the diagnostics in different experimental conditions. The experiments were performed in ohmic discharges in two scenarios: in discharges with LH-transition (working gas – deuterium) and in discharges with gas puffing modulation (working gas – hydrogen).