He–ICR cleanings on full metallic walls in EAST full superconducting tokamak

Abstract He–ICR cleanings were successfully carried out in 2006–2007 on the full superconducting tokamak (EAST), which is an ITER-relevant experimental tokamak. Factors influence on He–ICR efficiency, such as magnetic field, ICRF power and working pressure were investigated. In EAST, the breakdown pressure for He–ICR cleanings could reach 10 Pa. The removal efficiency for H during 20 kW 4.5 × 10−3 Pa He–ICR cleaning was same as that in He–GDC cleaning (2 Pa, 4A). Highest H removal rate in EAST with full metallic material walls, 1.7 × 1022 H/h in 20 kW 3 × 10−2 Pa He–ICR, was higher by a factor of four than that in HT-7 with carbon limiter configuration.