The m = 1 resistive mode for a tokamak plasma with large aspect ratio is considered: the dynamic equations in a resistive layer are solved by means of an asymptotic expansion for values of the growth rate in a suitable range. The eigenvalues characterizing the perturbation are found by means of a series expansion and it is shown that the main contribution to the expression of the eigenvalues is given by the first and the second order of this expansion. This method is different from the one used in the paper [G. Ara et al., Ann. Phys. 112, 443 (1978)], and can be applied in more general situations. © EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2016.
|Titolo:||Analysis of MHD instabilities by asymptotic methods: WKB expansion|
|Data di pubblicazione:||2016|
|Appare nelle tipologie:||1.1 Articolo in rivista|