Feasibility Study: High-k Temperature (HiT) Fluctuation Diagnostic

White, Anne; Chen, Xiang

doi:10.2172/1958406

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DOE OSTI · 1958406

Feasibility Study: High-k Temperature (HiT) Fluctuation Diagnostic

White, Anne·Chen, Xiang

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Abstract

The objective of the proposed research was to explore the feasibility of making measurements of high-k (electron-scale, ETG-relevant) electron temperature fluctuations in the core plasma of tokamaks and stellarators. We found that soft X-ray imaging combined with our novel pseudolocal tomographic algorithm enables local measurements of low-k (ion-scale, ITG/TEM and KBM/MTM relevant) electron temperature fluctuations in spherical tokamaks. The design parameters needed to consider deploying this new diagnostic are presented, and predictions for what the diagnostic would measure in L-mode and H-mode plasmas at NSTX-U, a high performance spherical tokamak in the USA, suggest that the new diagnostic can be used to study turbulence and transport over a wide range of plasma parameters, such as collisionality and plasma beta.

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70 PLASMA PHYSICS AND FUSION TECHNOLOGY CGYRO nonlinear gyrokinetics NSTX-U soft X-ray imaging spherical tokamak Tokamak turbulence

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White, Anne, Chen, Xiang. 2023-02-26. Feasibility Study: High-k Temperature (HiT) Fluctuation Diagnostic. https://doi.org/10.2172/1958406

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