Layout and results from the initial operation of the high-resolution x-ray imaging crystal spectrometer on the Large Helical Device

Journal Article · Wed Aug 15 00:00:00 EDT 2012 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.4744935· OSTI ID:22093703

Pablant, N. A.; Bitter, M.; Delgado-Aparicio, L.; Hill, K. W.; Lazerson, S.; Roquemore, A. L.; Gates, D.; Monticello, D.; Nielson, H.; Reiman, A. ^[1]; Goto, M.; Morita, S.; Yamada, H. ^[2]; Reinke, M.; Rice, J. E. ^[3]

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1. Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)
2. National Institute for Fusion Science, Toki 509-5292, Gifu (Japan)
3. Plasma Science Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307 (United States)

First results of ion and electron temperature profile measurements from the x-ray imaging crystal spectrometer (XICS) diagnostic on the Large Helical Device (LHD) are presented. This diagnostic system has been operational since the beginning of the 2011 LHD experimental campaign and is the first application of the XICS diagnostic technique to helical plasma geometry. The XICS diagnostic provides measurements of ion and electron temperature profiles in LHD with a spatial resolution of 2 cm and a maximum time resolution of 5 ms (typically 20 ms). Ion temperature profiles from the XICS diagnostic are possible under conditions where charge exchange recombination spectroscopy (CXRS) is not possible (high density) or is perturbative to the plasma (low density or radio frequency heated plasmas). Measurements are made by using a spherically bent crystal to provide a spectrally resolved 1D image of the plasma from line integrated emission of helium-like Ar{sup 16+}. The final hardware design and configuration are detailed along with the calibration procedures. Line-integrated ion and electron temperature measurements are presented, and the measurement accuracy is discussed. Finally central temperature measurements from the XICS system are compared to measurements from the Thomson scattering and CXRS systems, showing excellent agreement.

• OSTI ID: 22093703
• Journal Information: Review of Scientific Instruments, Vol. 83, Issue 8; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
CHARGE EXCHANGE
CONFIGURATION
DIAGNOSTIC TECHNIQUES
ELECTRON TEMPERATURE
EMISSION
ION TEMPERATURE
LHD DEVICE
PLASMA
PLASMA DENSITY
PLASMA DIAGNOSTICS
RADIOWAVE RADIATION
RECOMBINATION
SPATIAL RESOLUTION
SPECTROMETERS
SPECTROSCOPY
TEMPERATURE MEASUREMENT
THOMSON SCATTERING
TIME RESOLUTION
TOKAMAK DEVICES
X RADIATION