The long wavelength limit of the ion-temperature-gradient mode in tokamak plasmas
The stability of the ion temperature gradient mode in tokamak geometries is examined in the limit of long wavelength and flat density, retaining the non-adiabatic electron response. The existence of three unstable branches is shown. The toroidicity-induced branch tends to be stabilised for increasing wavelength by the finite e(Ti)(e(Ti)=L(Ti)/R) corrections. Meanwhile, the slab-like branch remains unstable and is hardly affected by the electron dynamics. The third branch corresponds to toroidicity-induced eigenmodes propagating in the electron diamagnetic direction, which are destabilised by the non-adiabatic electron dynamics. At shorter wavelengths, the toroidicity-induced branch remains strongly unstable, while the other two branches become stabilised.
Bibliographic Reference: Report: RT/FUS/89/27 EN (1989) 11 pp.
Availability: Available from Servizio Studi e Documentazione, ENEA, Centro Ricerche Energia Frascati, C.P.65-00044 Frascati, Roma (IT)
Record Number: 199110608 / Last updated on: 1994-12-02
Original language: en
Available languages: en