Predictive Fokker-Planck Modelling of Confined and Lost Fusion Alpha Particles in ITER
The paper represents results of predictive 3D Fokker-Planck modelling of phase space distributions of fusion alpha particles for basic ITER scenarios . We simulate the poloidal profiles of alpha induced current as well as of the fusion power deposition to bulk plasma electrons. It is demonstrated that anisotropy of velocity distributions of alphas results in a rather strong alpha driven current that makes up about 10-15% of the equilibrium plasma current density in the 4th ITER scenario. We investigate the impact of the alpha driven current on the ITER magnetic configuration. In the 4th scenario fusion alphas are shown to result in ~15% enhancement of the rotational transform and in ~11% enlargement of the Shafranov shift of magnetic flux surfaces. Also we evaluate the capability of gamma diagnostics of high-energy alphas in ITER and examine the collisional losses of fusion alpha particles.