Kinetics of He bubbles growth in W(110): impact of W temperature during irradiation and He incident energy

Irradiation of the first wall tungsten (W) materials by He is a crucial parameter to consider for the application of nuclear fusion to energy production, with one major consequence being the modification of the cristalline structure, along with formation and growth of He bubbles under the W surface. Complementary to post-mortem TEM and GISAXS analysis, this experiment allows the observation of the kinetics and dynamics of the He bubbles growth by in situ GISAXS measurements, along with characterization of their shape (e.g. faceting) from the form factor and the spatial distribution for the interference peak position. GISAXS measurements are complemented with GIXD to estimate the strain field induced by the bubbles in the subsurface region of the W crystal. For this proposal, we aim at getting closer to the experimental conditions in tokamaks, by studying the impact of W temperature during He exposure and incident He energies below/above the displacement energy threshold of W by He.