Density pump-out has been observed on the experimental advanced superconducting tokamak under the conditions of mitigated or totally suppressed edge localized modes with n = 2 external resonant magnetic perturbation (RMP), associated with decreased core density and degradation of particle confinement. In order to investigate the particle transport during RMP induced density pump-out, density modulation using supersonic molecular beam injection is performed to obtain the particle transport coefficients. The results show that the diffusive coefficient becomes larger and the inward convection velocity decreases towards the plasma edge after RMP. The measured radial electric field (Er) became less negative in the plasma edge near rho ~ 0.97 and consequently, the E × B shearing rate was reduced significantly, which is consistent with increased density fluctuations.
密度ポンプアウトは、n = 2の外部共鳴磁場摂動(RMP)により周辺局在モードが緩和または完全に抑制された条件下で、実験先進超伝導トカマクにおいて観測されており、コア密度の低下と粒子閉じ込めの劣化を伴う。RMP誘起密度ポンプアウト中の粒子輸送を調べるために、超音速分子ビーム入射を用いた密度変調を実施し、粒子輸送係数を取得した。結果は、RMP後、拡散係数が大きくなり、プラズマ周辺部に向かって内向き対流速度が減少することを示している。測定された径方向電場(Er)は、rho ~ 0.97付近のプラズマ周辺部で負の値が小さくなり、その結果、E × Bせん断速度は有意に減少し、これは密度揺動の増大と一致する。