Generation of zonal flow (ZF) by energetic particle (EP) driven toroidal Alfvï¿½n eigenmode (TAE) is investigated using nonlinear gyrokinetic theory. It is found that nonlinear resonant EP contribution dominates over the usual Reynolds and Maxwell stresses due to thermal plasma nonlinear response. ZF can be forced driven in the linear growth stage of TAE, with the growth rate being twice the TAE growth rate. The ZF generation mechanism is shown to be related to polarization induced by resonant EP nonlinearity. The generated ZF has both the usual meso-scale and micro-scale radial structures. Possible consequences of this forced driven ZF on the nonlinear dynamics of TAE are also discussed.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
Qiu, Z., Chen, L., & Zonca, F. (2016). Effects of energetic particles on zonal flow generation by toroidal Alfvï¿½n eigenmode. Physics of Plasmas, 23(9), -. . https://doi.org/10.1063/1.4962997