Alfvén frequency modes and global Alfvén eigenmodes
The spectrum of n = 0 Alfvén modes is calculated analytically and numerically in cylindrical and toroidal geometries. It includes global Alfvén eigenmodes (GAE) and surface modes (SM) of the fast magnetoacoustic wave. These modes are not induced by toroidicity. Then n = 0 GAEs owe their existence to shear. The frequency spacing between different radial and poloidal modes and the correlation of eigenfrequencies with changes in the edge density are examined and found to be in complete agreement with experimental observations of what have been named the Alfvén frequency modes. Although the eigenfrequency is related to the edge density, the n = 0 GAEs (AFM) are not necessarily edge localized.
Bibliographic Reference: Article: Nuclear Fusion, Vol. 37 (1997) No. 3, pp. 351-360
Record Number: 199710556 / Last updated on: 1997-05-09
Original language: en
Available languages: en