Neutral beam driven global Alfvén eigenmodes in the Wendelstein W7-AS stellarator
During neutral beam injection coherent magnetohydrodynamic activity occurs at low and medium beta, which is driven by the energetic beam particles. An interpretation is given in terms of marginally stable global Alfvén eigenmodes (GAE), which are destabilised by Landau resonances of the fast circulating particles. Toroidicity induced gaps for toroidal Alfvén eigenmodes do not occur in W7-AS, but GAE modes in gaps below the shear Alfvén continua can be excited. This is investigated within a gyrofluid model, which has previously been used for tokamak cases.
Bibliographic Reference: Article: Physical Review Letters, Vol. 72 (1994) No. 8, pp. 1220-1223
Record Number: 199410575 / Last updated on: 1994-11-28
Original language: en
Available languages: en