The kinetic theory of low-frequency Alfvén modes in tokamaks is presented. The inclusion of both diamagnetic effects and finite core-plasma ion compressibility generalizes previous theoretical analyses (Tsai S T and Chen L 1993 Phys. Fluids B 5 3284) of kinetic ballooning modes and clarifies their strong connection to beta-induced Alfvén eigenmodes. The derivation of an analytic mode dispersion relation allows us to study the linear stability of both types of modes as a function of the parameters characterizing the local plasma equilibrium and to demonstrate that the most unstable regime corresponds to a strong coupling between the two branches due to the finite thermal ion temperature gradient. In addition, we also show that, under certain circumstances, non-collective modes may be present in the plasma, formed as a superposition of local oscillations which are quasi-exponentially growing in time. © 1996 IOP Publishing Ltd.
All Science Journal Classification (ASJC) codes
- Nuclear Energy and Engineering
- Condensed Matter Physics
Zonca, F., Chen, L., & Santoro, R. A. (1996). Kinetic theory of low-frequency Alfvén modes in tokamaks. Plasma Physics and Controlled Fusion, 38(11), 2011 - 2028. https://doi.org/10.1088/0741-3335/38/11/011