Impurity sputtering model for ICRF edge plasma–surface interactions

Abstract One of the primary concerns associated with ion cyclotron resonance heating (ICRH) is the enhanced impurity sputtering resulting from radio frequency (RF) sheath formation near plasma-facing components (PFCs), such as limiters. Developing a sputtering model integrated with RF sheath simulations allows for a more comprehensive understanding of the kinetic behavior of incident ions and their interactions with the limiter surface. We accordingly develop an impurity sputtering model “PMSAD”, which computes the sputtering yield (amount of impurity) on the limiter surface based on incident ion characteristics and predicts the spatial distribution of impurities. The model provides a robust method for understanding and analyzing the impurity sputtering process from limiter surfaces, which is crucial for preventing ICRH surface erosion and reducing edge and core plasma contamination.