Abstract
A kinetic model for second harmonic electron cyclotron breakdown in stellarators, based on the results obtained from non-linear wave-particle interaction theory, is presented. A set of particle balance equations that describes the H2 ionization chain by means of an electron momentum space discretization is introduced and solved by numerical integration. The time evolution of the various species densities is determined and breakdown related predictions are obtained for different prefill pressure conditions and different values of injected power. Analysis of the TJ-II stellarator experimental data shows good agreement with the theoretical results. This is the first time, to the authors' knowledge, that precise predictions are directly compared with experimental behaviour.