Impurity Transport in Reversed Shear Plasmas of JT-60U and ELMy H-Mode

The particle transport for several impurity ion species was investigated in reversed shear and ELMy H-mode plasmas on JT-60U. Particle diffusivity for neon was evaluated from gas-puffing modulation experiments; the diffusivity was smaller by one order of magnitude at the internal transport barrier in reversed shear plasmas than in ELMy H-mode plasmas. An increase of the inward pinch velocity for neon was observed at the internal transport barrier in the reversed shear plasma. The particle transport coefficients at the internal transport barrier were compared for neon, carbon and helium. The particle diffusivity was almost the same for all ions, while the inward pinch velocity was larger for ions having higher charge state.