Author/Authors :
Kubo، نويسنده , , H. and Sakurai، نويسنده , , S. and Higashijima، نويسنده , , S. and Takenaga، نويسنده , , H. and Itami، نويسنده , , K. and Konoshima، نويسنده , , S. and Nakano، نويسنده , , T. and Koide، نويسنده , , Y. and Asakura، نويسنده , , N. and Shimizu، نويسنده , , K. Sydny Fujita، نويسنده , , T. and Hill، نويسنده , , K.W.، نويسنده ,
Abstract :
In order to extend the high-confinement reversed shear regime with an internal transport barrier (ITB) toward high radiation loss power, Ne and Ar injection have been investigated in JT-60U. With Ne injection, high confinement (H89PL>2.4, HH98(y,2)>1.6) and high radiation loss power fraction (>80%) were simultaneously obtained at high density (>0.7nGW). The radiation loss power was enhanced both in the main plasma and in the divertor plasma. With divertor plasma detachment and an X-point MARFE, the ITB was pronounced and the H89PL factor reached 1.8. However, Ar injection resulted in excessive radiation loss enhancement inside the ITB. The Ne and the C density profile were similar to the electron density profile, and their accumulation was not significant. On the other hand, Ar showed accumulation inside the ITB.
Keywords :
Internal transport barrier , Impurity transport , JT-60U , Radiation losses , Reversed shear plasma , Impurity injection
