Kinetic effects on the stability properties of field-reversed configurations. II. Nonlinear evolution

The nonlinear evolution of the magnetohydrodynamic (MHD) instabilities in kinetic field-reversed configurations (FRC) was analyzed. The linear and nonlinear stability of MHD modes with toroidal mode numbers n≥1 was investigated. Due to ion spin-up in the toroidal direction, the n≥ rotational modes were observed to grow during the nonlinear phase of the tilt instability. It was found that large-s̄ simulations show no saturation of the tilt mode, and there is slow nonlinear evolution of the instability after the initial fast linear growth.