The status of atomic models for beam emission spectroscopy in fusion plasmas

Considerable theoretical efforts have been undertaken in the last few years to resolve discrepancies between the modelled and observed spectra of beam emission in fusion plasmas. The experimental verification of the new theoretical data followed at the tokamaks JET and ALCATOR-C Mod. The lines ratio of the σ and π components of the motional Stark effect (MSE) were compared with the theoretical predictions. Though an overall good agreement with the experimental data was achieved, some questions still exist. In this paper, we summarize the current status of atomic models in the description of beam-emission spectra in fusion plasmas and point out the future need for atomic data in active plasma diagnostics