M.Yoshinuma, K.Ida, M.Yokoyama, C.Suzuki, M.Osakabe, H.Funaba, K.Nagaoka, S.Morita, M.Goto, N.Tamura, S.Yoshimura, Y.Takeiri, K.Ikeda, K.Tsumori, H.Nakano, O.Kaneko, and LHD Experiment Group
Impurity transport of ion ITB plasmas on LHD
Date of publication:
22 IAEA Fusion Energy Conference, EXC/9-1
Impurity hole, which is an extremely hollow profile of carbon impurity, is observed associated with increase of ion temperature gradient in the Large Helical Device (LHD). Difference of convection velocity in the magnetic axis position is clearly observed. It is suggested that the impurity hole becomes strong as the magnetic axis is shifted outward. The dependence of the impurity hole on the charge number, Z, is observed and the profile of higher Z impurity becomes more hollowed.