中文摘要：

<正> Internal reconnection event（IRE）,which is characterized by a perturbation inplasma current IP,loop voltage Vloop,Hα radiation and magnetic perturbation dBp,was observedin the SUNIST experiment.It is found that,the fluctuation before IREs is characterized by astructure of m=2/n=1,then changes torn=4/n=1 during the IREs;and,after IREs,themode number changes to m=3/n=1.An analysis in the evolution of equilibrium parametersduring IREs shows that a positive spike appears in the evolution of the plasma’s elongation anda negative spike in the poloidal beta of plasma.A collapse in the pressure profile,correspondingto the occurrence of IREs,is also found.

英文摘要：

Internal reconnection event （IRE）, which is characterized by a perturbation in plasma current Ip, loop voltage Vloop, Hα radiation and magnetic perturbation dBp, was observed in the SUNIST experiment. It is found that, the fluctuation before IREs is characterized by a structure of m= 2/n = 1, then changes to m = 4/n = 1 during the IREs; and, after IREs, the mode number changes to m = 3/n = 1. An analysis in the evolution of equilibrium parameters during IREs shows that a positive spike appears in the evolution of the plasma＇s elongation and a negative spike in the poloidal beta of plasma. A collapse in the pressure profile, corresponding to the occurrence of IREs, is also found.