Resonant interaction of energetic ions with Alfvén-like perturbations in stellarators
The modification of passing guiding centre orbits of 3.5 MeV alpha particles and 45 keV protons in the presence of global Alfvén eigenmodes (GAEs) is studied in modular advanced stellarators. It is found that if resonances between particles and waves occur, drift surfaces form a set of island structures. The mode numbers of the perturbations, which are dangerous for the energetic particle confinement, are discussed for two particular stellarators (Helias reactor and Wendelstein 7-AS). The perturbation amplitudes corresponding to the onset of orbit stochasticity are studied numerically. The coefficient of the collisionless stochastic diffusion is estimated using the analytically derived island width.
Bibliographic Reference: Report: IPP 2/326 EN (1994) 25 pp.
Availability: Available from Max-Planck-Institut für Plasmaphysik, 8046 Garching bei München (DE)
Record Number: 199410755 / Last updated on: 1994-11-28
Original language: en
Available languages: en