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Title: X-ray and extreme ultraviolet spectroscopy on DIII-D

Abstract

Two spectrometers were installed to measure tungsten emission in the core of DIII-D plasmas during a metal rings experimental campaign. The spectral range of the high-resolution (1340 spectral channels), variable-ruled grating X-ray and Extreme Ultraviolet Spectrometer (XEUS) extends from10–71$$\dot{A}$$ . The spectral range of the second spectrometer, the Long-Wavelength Extreme Ultraviolet Spectrometer (LoWEUS), measures between 31–174$$\dot{A}$$ . Three groups of tungsten lines were identified with XEUS: W 38+-W 45+ from 47–63$$\dot{A}$$ , W 27+-W 35+ from 45–55$$\dot{A}$$ , and W 28+-W 33+ from 16–30$$\dot{A}$$ . Emission lines from tungsten charge states W 28+, W 43+, W 44+, and W 45+ are identified and the line amplitude is presented versus time. Peak emission of W 43+-W 45+ occurs between core Te=2.5-3 keV, and peak emission of W28+ occurs at core Te 1:3 keV. One group of tungsten lines, W 40+-W 45+, between 120–140$$\dot{A}$$ , was identified with LoWEUS. W 43+- W 45+ lines measured with LoWEUS track the sawtooth cycle. Furthermore, sensitivity to the sawtooth cycle and the correlation of the peak emission with core electron temperature show that these spectrometers track the on-axis tungsten emission of DIII-D plasmas.

Authors:
 [1];  [1];  [1];  [1]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE Office of Nuclear Energy (NE)
OSTI Identifier:
1363906
Grant/Contract Number:
FC02-04ER54698; AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Instrumentation
Additional Journal Information:
Journal Volume: 12; Journal Issue: 06; Journal ID: ISSN 1748-0221
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; plasma diagnostics; x-ray spectroscopy; interferometry, spectroscopy and imaging

Citation Formats

Victor, Brian S., Allen, Steve L., Beiersdorfer, P., and Magee, E. W.. X-ray and extreme ultraviolet spectroscopy on DIII-D. United States: N. p., 2017. Web. doi:10.1088/1748-0221/12/06/C06011.
Victor, Brian S., Allen, Steve L., Beiersdorfer, P., & Magee, E. W.. X-ray and extreme ultraviolet spectroscopy on DIII-D. United States. doi:10.1088/1748-0221/12/06/C06011.
Victor, Brian S., Allen, Steve L., Beiersdorfer, P., and Magee, E. W.. 2017. "X-ray and extreme ultraviolet spectroscopy on DIII-D". United States. doi:10.1088/1748-0221/12/06/C06011.
@article{osti_1363906,
title = {X-ray and extreme ultraviolet spectroscopy on DIII-D},
author = {Victor, Brian S. and Allen, Steve L. and Beiersdorfer, P. and Magee, E. W.},
abstractNote = {Two spectrometers were installed to measure tungsten emission in the core of DIII-D plasmas during a metal rings experimental campaign. The spectral range of the high-resolution (1340 spectral channels), variable-ruled grating X-ray and Extreme Ultraviolet Spectrometer (XEUS) extends from10–71$\dot{A}$ . The spectral range of the second spectrometer, the Long-Wavelength Extreme Ultraviolet Spectrometer (LoWEUS), measures between 31–174$\dot{A}$ . Three groups of tungsten lines were identified with XEUS: W38+-W45+ from 47–63$\dot{A}$ , W27+-W35+ from 45–55$\dot{A}$ , and W28+-W33+ from 16–30$\dot{A}$ . Emission lines from tungsten charge states W28+, W43+, W44+, and W45+ are identified and the line amplitude is presented versus time. Peak emission of W43+-W45+ occurs between core Te=2.5-3 keV, and peak emission of W28+ occurs at core Te 1:3 keV. One group of tungsten lines, W40+-W45+, between 120–140$\dot{A}$ , was identified with LoWEUS. W43+- W45+ lines measured with LoWEUS track the sawtooth cycle. Furthermore, sensitivity to the sawtooth cycle and the correlation of the peak emission with core electron temperature show that these spectrometers track the on-axis tungsten emission of DIII-D plasmas.},
doi = {10.1088/1748-0221/12/06/C06011},
journal = {Journal of Instrumentation},
number = 06,
volume = 12,
place = {United States},
year = 2017,
month = 6
}

Journal Article:
Free Publicly Available Full Text
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