In situ elastic recoil detection analysis of tungsten surfaces during ITER-like helium irradiation

Tungsten surfaces are subjected to helium plasma simulating a tokamak divertor environment in the Dynamics of ION Implantation and Sputtering Of Surfaces (DIONISOS) experiment. For this work, surfaces are analyzed in real-time during irradiation with in situ elastic recoil detection to gain dynamic helium concentration depth profiles. The extreme environment of the divertor simulator requires specific considerations to be implemented to retain the integrity of Ion Beam Analysis (IBA) techniques for surface analysis. The development of the in situ elastic recoil detection measurement technique and the implications of the results regarding the modeling of tungsten surface modification due to helium plasma irradiation will be discussed.