Fokker-Planck Simulation of Runaway Electron Generation in Tokamak Disruptions

Abstract

The runaway electron (RE) generation during tokamak disruptions is investigated by kinetic simulations. Specifically, three dimensional (two-dimensional in momentum space; one-dimensional in the radial direction) Fokker-Planck simulations are coupled with the self-consistent electric field caused by the disruptions. The thermal quench time is varied, and the results are compared with those of the steady-state solution of the RE generation rate. The hot-tail effect is enhanced when the thermal quench time is shorter than the electron slowing down time.