Simulation of Disruption Plasma Parameters for the Confinement Ability of Runaway Electrons

The presence of runaway electrons during the dis-ruption evolves into a runaway current, which carries a large amount of energy and will cause irreversible damage to the toka-mak device in case of an impact on the device wall, and thus re-quires attention. It is found that the plasma parameters before plasma disruption, such as the boundary safety factor, the mag-nitude of the toroidal magnetic field, and the electron density, af-fect the formation of the runaway current during the experiment, which can also be interpreted as affecting the confinement of the runaway electron seeds during thermal quench, but there is no relevant numerical simulation study yet. In this qaper, the exper-imental results are reproduced qualitatively using the NIMROD simulation code, and the runaway electron confinement during thermal quench is investigated using a test particle model. Dif-ferent parameters are found to affect the runaway electron con-finement in their respective ways.