Current status of atomic physics data for the diagnosis of erosion using low charge states of tungsten and molybdenum*

Spectroscopic techniques to measure erosion and transport for high-Z plasma facing components require accurate atomic data. The near neutral ion stages are most critical for erosion diagnostics, requiring non-perturbative calculations. The first datasets for W and Mo used a number of approximate methods, perturbative approaches, and selected non-perturbative calculations. In recent years there have been large-scale non-perturbative calculations for low charge states of W and Mo. We present a review of the new data. This includes recent R-matrix excitation calculations for neutral W, W³⁺, neutral Mo, and Mo⁺. Ionization calculations include time-dependent close-coupling calculations for neutral W and W⁺, along with R-matrix calculations for W⁺, W²⁺, and a metastable of neutral W. The new data represents a significant improvement over the previously available S/XB, emissivity and effective ionization data.