Experimental study of the cold front propagation in the plasma shut-down experiment in the J-TEXT tokamak

Mitigation of major disruptions is essential in achieving fusion energy as a commercial energy source. Many tokamaks are using massive gas injection (MGI) as the disruption mitigation method since it is the most prospective potential disruption mitigation technique at present. However, mitigation efficiency by gas jet is limited by the shallow penetration of the gas jet which results in low gas mixing efficiency. In order to improve the mixture efficiency, the propagation of the cold front induced by supersonic molecular beam injection and the interaction between the cold front and the q = 2 surface have been studied in the J-TEXT tokamak. (papers)