Alpha particle driven current and torque in ITER baseline scenarios with 3D perturbations

In this paper three-dimensional (3D) kinetic Monte Carlo orbit-following simulations are carried out with the ASCOT code to estimate the alpha particle driven current and torque profiles in ITER baseline scenarios. Several different 3D magnetic field configurations, including TF ripple, ferritic inserts, test blanket modules and edge localized mode coil perturbations, are used in these simulations. The alpha particle current is found to be less than one percent for all configurations and scenarios. In axisymmetric magnetic field configurations, the collisional and j x B torque components cancel each other, whilst in non-axisymmetric cases, the total torque is nonzero. The total alpha driven torque is found to oppose that generated by the neutral beam injection particles and to be an order of magnitude smaller. Consequently, alpha particles will not significantly contribute to the plasma current nor act as a source of plasma rotation in the ITER baseline scenarios considered.