Disruptions, Runaway Electrons, and Electromagnetic Loads in a Compact Spherical-Tokamak Breeder: A Reduced-Order Assessment on a NIMROD-Verified Equilibrium

A reduced-order assessment of disruptions, runaway electrons, and electromagnetic loads for the compact spherical-tokamak breeder, on a NIMROD-verified equilibrium. Current-quench time 7-19 ms; a SEVERE runaway-electron avalanche (E/E_c about 1128, a beam of order 70 percent of plasma current); halo current 35 percent of plasma current. The conclusion is a hard design requirement: shattered-pellet-class disruption mitigation triggered within the current-quench window. The disruption risk is not claimed negligible.