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Title: The charge exchange recombination spectroscopy diagnostic on the upgraded Lithium Tokamak eXperiment (LTX-β )

Journal Article · · Review of Scientific Instruments
DOI: https://doi.org/10.1063/1.5039368 · OSTI ID:1484240

The Lithium Tokamak eXperiment has undergone an upgrade to LTX-β, a major part of which is the addition of neutral beam injection (NBI). NBI has allowed for a new charge exchange recombination spectroscopy (CHERS) system to be installed in order to measure impurity concentrations, ion temperature, and toroidal velocity. Previously on LTX measuring these parameters relied on passive spectroscopy and inversion techniques and had large uncertainty. The CHERS system has 52 total views, split into four groups of 13, half facing toward the beam and half symmetrically facing away from the beam, so the background non-beam related emission can be simultaneously subtracted. Both sets of views sample a major radius of 27-59 cm, with resolution through the beam of 1.5-2.5 cm. LTX-β is expected to have its magnetic axis near 35 cm, with minor radii of 18-23 cm. Three separate spectrometers will be used for the diagnostic, giving the system great flexibility to simultaneously measure emission from multiple impurity lines. The viewing optics are f/1.8, allowing all of the spectrometers to be fully illuminated. In conclusion, design and calibration of the system as well as the advantages of various configurations of the spectrometers will be highlighted.

Research Organization:
Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
Sponsoring Organization:
USDOE
Grant/Contract Number:
AC02-09CH11466; AC05-00OR22725
OSTI ID:
1484240
Journal Information:
Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 10 Vol. 89; ISSN 0034-6748
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English

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