Ion Heat Pulse after Sawtooth Crash in the JFT-2M Tokama

"The ion heat pulse after sawtooth crash is studied with the time-of-flight neutral measurement on the JFT-2M tokamak. The rapid change of the bulk ion energy distribution near the edge is observed after sawtooth crash. The delay time is measured and the effective measurlng position is estimated by a neutral transport code, then the thermal-conductivity, X_i^HP of about 15pml0m^2/sec is evaluated for the L-mode plasma . The simple diffusive model with constant X_i^HP, however does not explain the amplitude of the pulse in the ion energy distribution.