Assessment of atomic data for plasma modelling and effects of difference in atomic data on modelling results

Of important atomic processes taking place in tokamak plasmas, rate coefficient formulas available for ionization and recombination are briefly reviewed and those for oxygen and iron ions are studied by comparison. As an example, assessment of rate coefficient formulas for an impurity transport modelling based on a one-dimensional tokamak model is made, and the remarkable dependence of the radial impurity distributions on the difference between two dielectronic recombination rate coefficient formulas is shown. This result suggests that considerably accurate atomic data would be necessary to derive reliable values of anomalous impurity transport coefficients from plasma modelling research. (author)