Fast multiline low-Z impurity imaging diagnostic for fluctuation and particle confinement studies

A system for imaging complete tokamak edge cross sections using radiation from intrinsic low-Z impurities, such as carbon, with a frequency response of 500 kHz and a spatial resolution of 1--4 cm (depending on the thickness of the radiating region) is being developed. The noise level is determined by the electronics and is ≤2% for the full 500 kHz bandwidth and ≤1% for a 100 kHz subset of that bandwidth. Photon noise is 0.3% for the full 500 kHz bandwidth. This diagnostic can be used for studying fluctuations in Prad(λ), Γz, and Te. Additionally it may be useful for studying marfes and detached plasmas, transport and oscillations during pellet injection, and as a fast disruption precursor monitor