Measuring Te and ne in the poloidal plane using line ratios from puffed and intrinsic helium in TCV's divertor with the MANTIS diagnostic.

This work describes 2D measurements of n_e and T_e using neutral helium line ratios in the poloidal plane of TCV's divertor. He-I emissions from two singlet transitions, three triplet transitions, and a He-II line were simultaneously imaged for single-null deuterium plasmas with the MANTIS multi-spectral camera. Intrinsic helium and actively puffed helium were observed. The spectral images were inverted into 2D emissivity profiles. Collisional-radiative modeling of the emission was used to create 2D profiles of n_e and T_e. The profiles are compared against measurements from reciprocating Langmuir probes and a divertor Thomson scattering system. Providing unprecedented spatial coverage, this diagnostic technique is of great utility to plasma boundary research.

This work was supported by US DoE award DE-SC0020327.