Resonant energetic particles play a major role in determining the stability of toroidal Alfvén eigenmodes (TAE's) by yielding the well-known driving mechanism for the instability and by producing an effective dissipation, which removes the singular character of local oscillations of the shear-Alfvén continuum and gives discrete kinetic Alfvén waves (KAW's). Toroidal coupling of two counterpropagating KAW's generates the kinetic analog of the TAE, the KTAE (kinetic TAE). The nonperturbative character of this phenomenon and of the coupling between TAE and KAW's, and the relevance of finite drift-orbit effects limit the effectiveness of the analytical approach to asymptotic regimes, which are difficult to compare with realistic situations. A three-dimensional hybrid fluid-particle initial-value code for the numerical simulation of the linear and nonlinear evolution of toroidal modes of the Alfvén branch has been developed. It is shown that for typical parameters the KTAE is, indeed, more unstable than the TAE. © 1995 American Institute of Physics.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
Briguglio, S., Vlad, G., Zonca, F., & Kar, C. (1995). Hybrid magnetohydrodynamic-gyrokinetic simulation of toroidal Alfvén modes. Physics of Plasmas, 2(10), 3711 - 3723. https://doi.org/10.1063/1.871071