1999 年 75 巻 11 号 p. 1297-1304
Wall conditioning can control impurity and hydrogen isotope. So various methods of wall conditioning have been adopted in JT-60U. After the vacuum vessel is closed and pumping system works, tokamak discharges can be obtained within a week. The conditioning can also make a good condition that recycled particles are so low as to correspond to injected NB particles. An equivalent QDT up to 1.25 can be transiently achieved in reversed shear plasmas because of both optimization of wall conditioning and improved confinement. Wall conditioning in JT-60U is discussed in this paper.