Title: Resilience of Quasi-Isodynamic Stellarators against Trapped-Particle Instabilities
Author: Proll, J. H. E., et al
It is shown that in perfectly quasi-isodynamic stellarators, trapped particles with a bounce frequency much higher than the frequency of the instability are stabilizing in the electrostatic and collisionless limit.
The collisionless trapped-particle instability is therefore stable as well as the ordinary electron-densitygradient- driven trapped-electron mode. This result follows from the energy balance of electrostatic instabilities and is thus independent of all other details of the magnetic geometry.
PRL 108, 245002 (2012) PHYSICAL REVIEW LETTERS