The magnetic perturbations due to in-vessel coils, foreseen to mitigate edge-localized modes (ELMs) in ITER, could also compromise the confinement of energetic ions. We simulate the losses of fusion alpha particles and neutral beam injection-generated fast ions in ITER under the influence of the 3D perturbations caused by toroidal field coils, ferritic inserts, test blanket modules and ELM control coils (ECCs) with the ASCOT code. The ECCs are found to stochastize the magnetic field deep inside the pedestal in the 15 MA inductive reference operating scenario. Such a field is found insufficient to confine not only the fast but also the thermal ion population, leading to a strongly reduced fast ion source in the edge. Therefore, even with a stochastic edge, no high fast ion power loads are expected. However, the plasma response has not yet been included in the calculation of ITER magnetic background data, and it is probable that the perturbation is currently overestimated.
Fast ion transport during applied 3D magnetic perturbations on DIII-D