PHYSICAL DESIGN OF JT-60 SUPER UPGRADE

The JT-60 Super Upgrade (JT-60SU) is an upgraded tokamak device of JT- 60U for developing the steady-state reactor and advanced tokamak opera tion in the International Thermonuclear Experimental Reactor. The devi ce is planned to utilize the JT-60 facilities fully and to minimize th e needed modification. The major radius is 4.8 m and the maximum plasm a current is 10 MA. Neutral beam injection with 750 keV beam energy is the primary heating method. The machine is capable of steady-state op eration with high density up to 8.8 x 10(19) m(-3) at 5 MA plasma curr ent. The high operating density, over the Greenwald et al. limit, is c ritically important in order to achieve high bootstrap current fractio n. Ballooning mode and low n ideal magnetohydrodynamic (MHD) mode incl uding the bootstrap current were analyzed for steady-state operation. The current profile must be optimized to obtain a normalized beta up t o 3. The plasma configuration with high triangularity was adopted in o rder to get good MHD stability and high energy cofinement. A compact d ivertor was designed in order to get the large plasma space. (C) 1997 Elsevier Science S.A.