Alcator C-Mod is unique in the tokamak community with its capability to run diverted discharges using all molybdenum plasma facing components (PFCs). The impact of contamination from such high-Z elements can have significant effects on plasma power balance through increases in the radiated power. At C-Mod, research into impurity production and transport is ongoing. Currently, diagnostics are being designed and deployed to study the both the radial and poloidal distribution of impurities. A combination of experimental bolometry and spectroscopy measurements will be used in conjunction with emissions modeling from atomic physics codes to calculated the 2D impurity distribution for typical C-Mod plasmas. This measurement will be new for Alcator and will be used to investigate expected flux surface asymmetries in impurity density caused by toroidal rotation and intrinsic particle drifts.

Topics of interest include: VUV/SXR spectroscopy, tomography, impurity transport and emission modeling, disruption mitigation using high pressure gas injection.

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