Tritium AMS measurements have been firstly performed for studies in biology and medicine. Recently, AMS was upgraded for depth profiling. Such measurements are useful since Tritium has a great penetrability through different materials and its concentration may be low on the material surface but high in the bulk. While for standard AMS measurements no special precautions with respect to the sputtering process at the target are required, for depth profiling analysis the sputter erosion rate has to be uniform on the analyzed target area. Also, ions sputtered from the crater sides should not be included in the analysis because they do not reflect the concentration at the depth corresponding to the crater bottom. We performed our AMS measurements using the Upgraded Ultra Clean Injector (URI) of the Munich Accelerator Laboratory and the AMS-facility of the National Institute of Physics and Nuclear Engineering Bucharest. Part of the experiments was done to monitor the T concentration in the vicinity of nuclear power plants (CANDU-type) and in the environment of nuclear fuel reprocessing plants. Recently, because of the International Thermonuclear Experimental Reactor project (ITER), special interest is paid to depth profiling measurements of the Tritium created in D-D or D-T fusion reactions in magnetically confined plasmas, which is subsequently deposited in plasma facing components of the reaction chamber. The measurements were performed on long term samples (LTS) made of pyrolithic graphite, installed between the vessel wall protection tiles in the Tokamak experiments ASDEX-Upgrade (IPP Garching, Germany), and JET (Joint European Torus, Abingdon, UK). These measurements give detailed information about the spatial distribution of deuteron and triton fluxes to the vessel walls. Information has also been obtained about the plasma confinement and stability gained after the introducing of the CDH-mode (Completely detached Highly Confined mode). Toroidal and poloidal distributions of Tritium and Deuterium depth profiles provided information about the interaction of the heating Neutral Deuterium Beam with the confined, rotating plasma. Like this, we have produced the highest accuracy characterization of the plasma impact distribution on the divertor plates. The accumulation of tritium represents a critical radiological problem in future fusion devices like ITER. AMS measurements can contribute as a nuclear safeguard, providing radio-dosimetric information based on the precise inventory of the tritium deposition. Concluding, AMS demonstrates to be a sensitive diagnose tool for Tokamak fusion experiments and is a promising method to provide a useful diagnostic tool in the future ITER project.
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