Studies of the influence of electron heating on ITB subject to advanced tokamak operation in JT-60U

摘要

The influence of dominant electron heating on internal transport barriers (ITBs) was investigated in JT-60U. The electron cyclotron waves were mainly utilized in order to extend the experimental space into a dominant electron heating regime. The experiments were carried out on both reversed magnetic shear (RS) and positive magnetic shear (PS) plasmas. It was found that in RS plasmas clear ITBs in T_e, T_i and n_e profiles remained even under dominant electron heating. Energy confinement in excess of twice the H0mode scaling has been obtained in the regime. On the other hand, it was found that in PS plasmas the T_i ITB was degraded by dominant electron heating.