Relevance of heavy-impurity transport simulations of TFR Tokamak plasmas to ionisation equilibrium evaluations

Experimental absolute and relative line radiances of heavy impurities in the X-ray and VUV regions of the spectrum from low-density TFR plasmas are interpreted in terms of ionisation, recombination and diffusion. The authors conclude that it is necessary to use as adjustable parameters both diffusion terms and atomic rate coefficients (namely, the S/ alpha ratios). Fractional abundance curves have been calculated using the adjusted S/ alpha ratios for iron, and compared with theoretical IE calculations.