Impurity profiles and transport characteristics in JT-60U

In JT-60U, impurity profiles were measured with charge exchange recombination spectroscopy (CXRS) and impurity transport was analyzed. Density profiles of fully ionized carbon ions C6+ were obtained from neutral beam density profiles and excitation rate coefficients for CVI 529.0 nm (n=8-7). Peaked density profiles of C6+ in a typical NB heated deuterium plasma were measured. Peaking parameter Cv was not constant and was in the range of 0.5-1.0. O VII (1s2-2s2p, 2.16 nm) and O VIII (1s-2p, 1.90 nm) were measured with a grazing incidence spectrometer viewing the plasma center vertically. Oxygen impurity transport was analyzed in the peripheral region from the ratio of O VIII/O VII. (orig.)