Gamma-Ray Diagnostics at ITER Utilizing Tungsten as the First Wall Material

On July 17th, during scientific visit to the ASIPP, Prof. Alexander Shevelev delivered a presentation titled "Gamma-ray diagnostics at ITER with tungsten first wall." This subject matter was thoroughly examined and discussed, shedding light on the significant role of gamma-ray diagnostics in the realm of nuclear fusion research, particularly in the context of ITER, where tungsten serves as a crucial component of the first wall.

Prof. Alexander Shevelev, a researcher at the Ioffe Institute of the Russian Academy of Sciences, studied Nuclear Physics in St. Petersburg State Technical University and obtained his M.Sc. He earned his Ph.D. in Plasma Physics from the Ioffe Institute, specializing in gamma-ray and hard X-ray spectrometry of high temperature plasma. He studied runaway electrons and fast ions at various tokamaks and supervised the development of diagnostic equipment for plasma facilities. He led the Gamma-ray Spectrometry group at the Ioffe Institute and was a member of the Russian diagnostic team in the ITER Project. He published over 100 peer-reviewed publications and participated in numerous scientific conferences.

Report summary: ITER's first wall material change led to adjustments in energetic particle info extraction using gamma-ray spectrometry. Adjustments are minor as B-10 and B-11 isotope reactions can be analyzed. Spatial distribution of boron impurities is key. Gamma-ray spectrometer in NPA system provides info on fast particles in H and D plasma during SRO and FPO. Alpha particle diagnostics possible via 13C nucleus gamma-ray transitions. DT plasma gamma-ray measurements hindered by high-intensity background. Three-ion ICRF heating experiments may study MeV alpha particles pre-fusion. Fusion rate and runaway electron distribution info not significantly affected by first wall replacement.

Text by Victoria Saklakova