Transient and Intermittent Magnetic Reconnections
in TS-3/ 4 Tokamak Merging Experiments 

Y. Ono and TS-3 and 4 Group 
(High Temperature Plasma Center, University of Tokyo)

Fast/ transient magnetic reconnection has been studied at TS-3 and 4 
experiments by overcompressing two merging high-q (high guide field) tokamaks 
whose current sheet had the lowest resistivity[1-3]. The inflow flux was 
observed to pile up around the current sheet, causing its rapid growth and 
peaking around X-point. When the flux pileup exceeded the critical limit, 
the sheet was ejected mechanically from the squeezed X-point area. Note that 
the reconnection speed was relatively slow during the flux-pileup and became 
drastically fast during the ejection. The growth and ejection of current sheet 
both increased plasma inflow due to its mass accumulation and ejection, 
respectively. The varied inflow experiment revealed that the flux/ plasma 
inflows faster than the sheet dissipation/ plasma outflow transformed the 
quasi-steady reconnection though the transient one, finally to the 
intermittent one.

[1] Y. Ono et al. Phys. Fluids B. 6, 3691 (1993). 
[2] Y. Ono et al. Phys. Plasmas. 4, 1953 (1997).
[3] Y. Ono et al. Phys. Plasmas. 7, 1863 (2000).