Poloidal CX visible light plasma rotation diagnostics in TCV

Controlled thermonuclear fusion is the main goal of plasma physics. At the Swiss Plasma Center, the Tokamak `a Configuration Variable (TCV) constitutes the main experiment on fusion research, where high temperature plasmas are confined by means of magnetic fields. The confinement of plasma energy and particles is limited by transport arising from the gradients between the hot-dense plasma core and the cold-rarefied plasma edge. Due to the tokamak topology, plasma can rotate in the toroidal and poloidal directions. Plasma rotation has a strong influence on confinement and stability, which makes its understanding a priority. There are many discrepancies between the theoretical rotation description and experiments, which stimulated research in the field. In this context this work provided experimental results of unprecedented accuracy, where plasma impurity parameters are measured with the charge exchange recombination spectroscopy (CXRS) diagnostic. CXRS exploits the CX signal induced by a diagnostic neutral beam injector (DNBI), permitting localised measurements of impurity rotation, density and temperature. During this work, the CXRS diagnostic was extended with the development of a new high resolution system, termed CXRS-EDGE, devoted to the study of edge profiles. The accuracy improvements with respect to the legacy systems were obtained through an high throughput lens spectrometer and numerical aperture matching optics, resulting in rotation uncertainties