Nonlinear simulations of macro-instabilities in tokamak plasmas beyond MHD

The simulation of the interaction between macroscopic Alfvén modes and a population of hot ions is one of the challenges in tokamak plasma physics, mainly because of its possible negative impact on the plasma confinement in a future fusion device. The bi-fluid XTOR-2F code [1], using a fully implicit method with an iterative pre-conditioned Newton-Krylov for its solution at every time step has been extended to include one or several ion populations integrated in time by a PIC method. The originality of that code, XTOR-K, is the “exact” integration of the particle trajectories, i.e. resolving their gyro-motion. Both codes, XTOR-2F and XTOR-K, are now operational.