Characteristics of low-q disruptions in PBX

The results of this study indicate that even within the relatively narrow low-q/sub /psi// operating space, there is a continuum in the characteristics of the low-q/sub /psi// disruptions with a primary dependence on the value of <β/sub t/>. While the ideal external kink instability may give rise to the growing oscillations that lead up to the ultimate disruption, the instabilities are weighted towards the edge only at the lowest-q/sub /psi// (≤ 3) and highest <β/sub t/>. At even slightly higher q/sub /psi//, the oscillations are also seen, at the same frequency, in the interior of the plasma. The results further indicate that effects outside the scope of ideal MHD theory may play a significant role in low-q/sub /psi// disruptions. 34 refs., 19 figs