Abstract
A nonlinear bump-on-tail model for the growth and saturation of energetic particle driven plasma waves has been extended to include two populations of fast particles - one dominated by dynamical friction at the resonance and the other by velocity space diffusion. The resulting temporal evolution of the wave amplitude and frequency depends on the relative weight of the two populations. The two species model is applied to burning plasma with drag-dominated alpha particles and diffusion-dominated ICRH accelerated minority ions, showing the stabilization of bursting modes. The model also suggests an explanation for the recent observations on the TJ-II stellarator, where Alfvén Eigenmodes transition between steady state and bursting as the magnetic configuration varied.
| Original language | English |
|---|---|
| Article number | 122511 |
| Journal | Physics of Plasmas |
| Volume | 24 |
| Issue number | 12 |
| DOIs | |
| State | Published - Dec 1 2017 |
Funding
This work has been part-funded by the RCUK Energy Programme [Grant No. EP/P012450/1]. Support from the U.S. group was provided by the U.S. DOE under Grant No DE-FG02-99ER54563. This work has been part-funded by the RCUK Energy Programme [Grant No. EP/P012450/1]. Support from the U.S. group was provided by the U.S. DOE under Grant No DE-FG02–99ER54563.