摘要
The behavior of multiple modes before and during minor disruption with the external resonant magnetic perturbations(RMPs)has been studied on a J-TEXT tokamak.The main component of RMPs is m/n=2/1,where m and n are the numbers of the poloidal and toroidal modes,respectively.During the mode-locking caused by RMPs,it is found that before a minor or a major disruption(if there is no minor disruption),strong oscillations in both electron temperature and density occur if the edge safety factor q_(a)>3.The analysis shows that the oscillations are caused by the m/n=3/1 mode.In addition,using the ECE,Mirnov coils and 2D electron cyclotron emission imaging diagnostic systems,it is found that a thermal collapse occurs on the inner side of the 2/1magnetic island during the minor disruption,and before the collapse,a 3/2 island increases,after the collapse,the 3/2 island may disappear.Moreover,the study also shows that these 3/1,2/1 and 3/2modes play roles in the thermal collapse of disruptions.
基金
National MCF Energy R&D Program of China(No.2018YFE0310300)
National Natural Science Foundation of China(Nos.51821005,51977221 and 61903384)
Fundamental Research Funds for the Central Universities(No.CZY20028)
Startup Funds for the Introduction of Talents,South-Central Minzu University(No.YZZ19026)。
