Simulations and theories of relativistic ion cyclotron instabilities driven by MeV alpha particles in thermal deuterium plasmas

A study on the relativistic ion cyclotron instability at high harmonics driven by MeV alpha particles and the resultant alpha dynamics using particle-in-cell simulations, the kinetic theory and perturbation theory was presented. It was found that only alphas with perpendicular momentum above a threshold are involved in the wave-particle interaction. An explanation for the selective gyro-broadening based on the wave-alpha interaction calculated from the perturbation theory was presented.