Supersonic molecular beam injection effects on tokamak plasma applied non-axisymmetric magnetic perturbation

Abstract

The change of tokamak plasma behavior by supersonic molecular beam injection ( SMBI) was investigated by applying a three-dimensional magnetic perturbation that could suppress edge localized modes ( ELMs). From the time trace of decreasing electron temperature and with increasing plasma density keeping the total confined energy constant, the SMBI seems to act as a cold pulse on the plasma. However, the ELM behaviors were changed drastically ( i. e., the symptom of ELM suppression has disappeared). The plasma collisionality in the edge-pedestal region could play a role in the change of the ELM behaviors.