Ultrafast spectroscopy diagnostic to measure localized ion temperature and toroidal velocity fluctuations

2010-10-01
Uzun Kaymak, İlker Ümit
Fonck, R. J.
McKee, G. R.
Schoenbeck, N.
Smith, D.
Winz, G.
Yan, Z.
A dual-channel high-efficiency, high-throughput custom spectroscopic system has been designed and implemented at DIII-D to measure localized ion thermal fluctuations associated with drift wave turbulence. A large-area prism-coupled transmission grating and high-throughput collection optics are employed to observe C VI emission centered near lambda = 529 nm. The diagnostic achieves 0.25 nm resolution over a 2.0 nm spectral band via eight discrete spectral channels. A turbulence-relevant time resolution of 1 mu s is achieved using cooled high-speed avalanche photodiodes and ultralow-noise preamplifiers. The system sensitivity is designed to provide measurements of normalized ion temperature fluctuations on the order of delta T-i/T-i <= 1%. (C) 2010 American Institute of Physics. [doi:10.1063/1.3479114]

Citation Formats
İ. Ü. Uzun Kaymak et al., “Ultrafast spectroscopy diagnostic to measure localized ion temperature and toroidal velocity fluctuations,” REVIEW OF SCIENTIFIC INSTRUMENTS, vol. 81, no. 10, pp. 0–0, 2010, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/37992.