Simulations of gyrokinetic energetic ions interacting with the magneto-hydrodynamic (MHD) Alfvén Eigenmodes are presented. The effect of the finite fast-ion orbit width and the finite fast-ion gyroradius, the role of the equilibrium radial electric field, as well as the effect of anisotropic fast-particle distribution functions (loss-cone and ICRH-type distributions), are studied in Wendelstein 7-X stellarator geometry using a combination of gyrokinetic particle-in-cell and reduced MHD eigenvalue codes. A preliminary stability analysis of a HELIAS reactor configuration is undertaken.
Global linear gyrokinetic simulation of energetic particle-driven instabilities in the LHD stellarator