The carbon impurity particle transport in ohmic discharges on the HT-7 tokamak
The carbon impurity ohmic discharges on particle transport in the HT-7 tokamak

The line-integrated optical measurement of impurity radiation profiles for the study of light impurity transport is performed in the HT-7 tokamak. The carbon impurity line emissivity is obtained by Abel inversion. The radial transport behaviours of carbon impurities at different central line averaged electron densities \overline {n_\e} are investigated in ohmic discharges. The diffusion coefficient D_{k}(r), the convection velocity W_{k}(r) and the total flux of the impurity ions \Ga _{k} decrease with the increase of \overline {n_\e} , which shows a reduction in the impurity particle transport at higher electron densities.