Upgrade of the Analytical System for Studies of Plasma-Facing Components from a Tokamak

Sammanfattning: Fusion energy is a potential candidate for sustain-able steady-state energy supply. However, a fully functional fusion reactor is not yet available and several remaining challenges need to be addressed before fusion becomes a reliable source. One of the remaining challenges with fusion is the plasma-induced modification of the inner wall of the tokamak, i.e. the structures surrounding hot plasma. Due to the rarity of tritium, an important element in future fusion fuel, the plasma facing component (PFC) should have as low fuel retention as possible. In this thesis, methods for controlling ion accumulation in a material sample have been developed. Using the new system, a molybdenum (42Mo) target has been implanted with deuterium (2H) and the retention has been measured with ion beam analysis. The experiment was carried out using particle accelerators at the Ångström Laboratory at Uppsala University. Following tasks were completed before the experiment took place: (a) automation of the target position regulator, (b) development of control software, and (c) calibration and testing of the system. The deuterium dose was estimated at the level of1.9·1017 atoms/cm2.The deuterium concentration in molybdenum was found to be around 28·1015 atoms/cm2. This corresponds to a retention rate of around (15±3)%.