Recent Results in JT-60 Advanced Experiment JT-60 Team, JAERI (Presented by Naoyuki MIYA)

Major efforts in the recent JT-60 experiments have been concentrated on the improved confinement of plasmas with profile control and on the steady state operation study. Peaked density profiles were produced with the successive pellet injection. The energy confinement time was improved by 40% as large as that with the gas fuelled discharges. The fusion products n e(0)τET i(0)reached 1.2 × 1020m−3·s·keV, which was twice that of gas fuelled discharges. High-βp, plasmas were obtained in low-I p discharges with improved confinement and a high ion temperature T i, (0) of 12 keV. The bootstrap current reached 80% of the total plasma current at βp=3.2. The new concept of a steady-state tokamak power reactor has been proposed on the basis of this result. The maximum current drive efficiency ηCD of 3.4 × 1019m−2·MA/MW was obtained in the LH current drive experiments. Helium ash exhaust experiments using He-beam injection into H+ plasmas showed promising results for α-particle exhaust in a fusion power reactor.