Novel ion temperature fluctuation diagnostic using spectral correlation for turbulence studies in high temperature plasma

Ion temperature fluctuation measurements are key to turbulence studies, and localized main-ion temperature fluctuation measurements in the core provides crucial turbulence information and are difficult to detect at turbulence relevant speeds. To do so, a new diagnostic is being developed and benchmarked against traditional methods. Dispersive spectrometers have been standard for spectral analysis and to great success. There are however some key throughput limiters in the need for a slit and the losses through a dispersive element. Advanced analysis techniques can be applied to the data to improve the SNR, such as Linearized Spectra Correlation Analysis (LSCA), where spectral bins are grouped together to extract fluctuations in the gaussian caused by temperature and doppler shifts. Presented here are plans to create a diagnostic utilizing interference filters rather than dispersive elements to improve throughput in the diagnostic while retaining the capability for LSCA. This new interference filter diagnostic is compared to a traditional spectrometer approach, comparing SNR, minimum detectable fluctuations, and freedom in detector type and form factor.