Developing an iterative synthetic diagnosis workflow for light impurities on WEST

An iterative synthetic diagnosis workflow is developed to infer impurity sources and transport through the main Scrape Off Layer (SOL) plasma. Often, fusion devices are limited in poloidal diagnostic coverage. However, full knowledge of impurity distributions over the poloidal extent is necessary to interpret experimental results. The workflow starts with a fixed background plasma to be used by a SOL impurity transport code to determine poloidal charge state abundances. The collisional radiative code ColRadPy is used to convert these abundances to spectral line intensities. Raysect is used to account for both 3D effects of sightlines and reflections off in-vessel components. Experimental measurements are compared with synthetic ones from this workflow, then used to iterate free parameters in the impurity transport code to spatially adjust the gridded charge state distribution and find consistency between the synthetic and experimental results. Both experimental and SOLEDGE SOL power scans were conducted on WEST focusing on oxygen, which is assumed to dominate W sputtering. A direct comparison of measured O II emission shows good agreement with the constructed synthetic workflow. The synthetic diagnosis workflow is used to inform future measurements of higher charge states.