Coherence Imaging Spectroscopy Characterization on the CTH and W7-X Experiments

Two-dimensional profiles of line-integrated impurity emissivity and velocity in the Compact Toroidal Hybrid (CTH) experiment are obtained with Coherence Imaging Spectroscopy (CIS), a polarization interferometry technique with fixed delays. To characterize the optical setup, CIS observations are benchmarked against Doppler-shifted spectroscopy measurements. Spectroscopy confirmed toroidal He$^{\mathrm{+}}$flows of 10-15 km/s while also identifying contaminating lines within the CIS spectral filter and associated errors.Additionally, two CIS instruments investigating the 3D physics of the W7-X island divertor provide ion flow measurements in orthogonal directions.A continuously tunable laser and wavemeter supply an absolute reference during W7-X plasma operations to simplify analysis and allow for measurements of multiple ion species. He$^{\mathrm{+}}$flow profiles and their comparison to C$^{\mathrm{+\thinspace }}$flow structures in the W7-X divertor will be presented.