Effect of Energetic Trapped Particles Produced by ICRF Wave Heating on Sawtooth Instability in the DIII-D Tokamak

We evaluate the accuracy of the Porcelli sawtooth model using more realistic numerical models from the ORBIT‐RF and GATO codes in DIII‐D fast wave heating experiments. Simulation results confirm that the fast wave‐induced energetic trapped particles may stabilize the sawtooth instability. The crucial kinetic stabilizing contribution strongly depends on both the experimentally reconstructed magnetic shear at the q = 1 surface and the calculated poloidal beta of energetic trapped particles inside the q = 1 surface.