A fast charge coupled device detector for charge exchange recombination spectroscopy on the DIII-D Tokamak

Journal Article · Sat Feb 01 04:00:00 EST 1997 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.1147895· OSTI ID:450590

Thomas, D M; Burrell, K H; Groebner, R J; Gohil, P; Kaplan, D; Makariou, C; Seraydarian, R P ^[1]

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1. General Atomics, San Diego, California (United States)

Charge exchange recombination (CER) spectroscopy has become a standard diagnostic for Tokamaks. CER measurements have been used to determine spatially and temporally resolved ion temperature, toroidal and poloidal ion rotation speed, impurity density, and radial electric field. Knowledge of the spatial profile and temporal evolution of the electric field shear in the plasma edge is crucial to understanding the physics of the {ital L} to {ital H} transition. High speed CER measurements are also valuable for edge localized mode studies. Since the 0.52 ms minimum time resolution of our present system is barely adequate to study the time evolution of these phenomena, we have developed a new charge coupled device (CCD) detector system with about a factor of 2 better time resolution. In addition, our existing system detects sufficient photons to utilize the shortest time resolution only under exceptional conditions. The new CCD detector has a quantum efficiency of about 0.65, which is a factor of 7 better than our previous image intensifier-silicon photodiode detector systems. We have also equipped the new system with spectrometers of lower {ital f}/number. This combination should allow more routine operation at the minimum integration time, as well as improving data quality for measurements in the divertor-relevant region outside of the separatrix. Construction details, benchmark data, and initial Tokamak measurements for the new system will be presented. {copyright} {ital 1997 American Institute of Physics.}

• OSTI ID: 450590
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 2 Vol. 68; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BOUNDARY LAYERS
CHARGE EXCHANGE
CHARGE-COUPLED DEVICES
DESIGN
DIVERTORS
FABRICATION
ION TEMPERATURE
MAGNETIC CONFINEMENT
PLASMA DENSITY
PLASMA DIAGNOSTICS
PLASMA IMPURITIES
PLASMA INSTABILITY
QUANTUM EFFICIENCY
RECOMBINATION
TOKAMAK DEVICES