Experimental Measurement of Electron Heat Diffusivity in a Tokamak

Abstract
Electron temperature perturbations produced by internal disruptions in the center of the Oak Ridge Tokamak (ORMAK) are followed with a multichord soft-x-ray detector array. The space-time evolution is found to be diffusive in character, but the conduction coefficient determined from a heat-pulse-propagation model is larger by a factor of 2.5-15 than that implied by the measured gross energy-containment time.