Sawtooth oscillations in tokamaks frequently lead to the redistribution of energetic ions, mainly on passing orbits, causing their expulsion from the core. This paper discusses the first measurements of the interaction of fast ions and sawteeth in the Large Helical Device. The crashes were caused by the plasma current induced by Electron Cyclotron Current Drive and Neutral Beam Current Drive. Despite these crashes, there was no detectable redistribution effect on fast ions in either the core or at the edge of the plasma.
This paper investigates the impact of sawtooth oscillations on fast ions in a stellarator device, the Large Helical Device. Sawtooth oscillations can often expel energetic ions from the core of tokamaks, but this study found no detectable redistribution of fast ions during these crashes in the stellarator, despite the presence of plasma current induced by Electron Cyclotron Current Drive and Neutral Beam Current Drive.