Resistive stability of canonical profiles

摘要

The stability of tearing modes for current profiles satisfying the principle of profile consistency found by Coppi is investigated using a simple cylindrical model and compared with tokamak data. Saturated magnetic islands may occur, leading to flat regions superimposed on the canonical profile, as recently observed in JET. However, depending on the values of the safety factor and internal inductance, the m/n = 2/1 and 3/2 modes may become simultaneously unstable, giving rise to the possibility of disruption triggered by island overlap