ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
The benchmark design for a high spatial resolution, high sensitivity, long-wavelength density fluctuation diagnostic that observes collisionally induced Lyman-alpha emissions (λ0(approximate)121.6 nm) from neutral beam atoms is presented. The sensitivity to plasma fluctuations at Lyα is estimated to be about 50 times higher than at Dα. This dramatically increases the photon-noise-limited signal-to-noise ratio. Design criteria include a spectral resolution of Δλ(approximate)0.5 nm at Lyα, to isolate the Doppler-shifted beam emission from the bright edge Lα emission; high quantum efficiency detectors; high optical throughput; multichannel capability in the radial and poloidal directions; spatial resolution near 1 cm in the radial and poloidal directions to measure fluctuations in the wave number range 0.1≤kr, kθ≤3 cm−1. A system design based on a Czerny–Turner monochromator is considered. © 2001 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1323246
