Non-inductive full current drive (CD) in a reversed magnetic shear (RS) plasma with high energy confinement of 1.4 times the H-mode scaling at 82% of the Greenwald density has been achieved simultaneously for the first time in a tokamak; these results were obtained in the JT-60U tokamak. The full-CD state was realized by a combination of waves in the lower hybrid range of frequency and neutral beam injection together with high bootstrap current fraction (fbs) of 62% to the total plasma current. The combination has demonstrated for the first time active current profile modification in a high fbs RS plasma both in the core and in the peripheral regions.
Overview of JT-60U results towards the establishment of advanced tokamak operation