Destruction of Magnetic Surfaces by Resonant Helical Windings

摘要

Helical winding current thresholds for the destruction of magnetic surfaces in large aspect-ratio tokamaks are estimated. The influence of magnetic islands created by external windings and by tearing instabilities on the disruptive instability is considered. The radial dependence of the perturbations and the change in the shear over the islands widths are taken into account. Ergodization due to secondary island's caused by the coupling between the resonant helical fields and the toroidal curvature are also considered. (Atomindex citation 20:017324)