skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: A fast-time-response extreme ultraviolet spectrometer for measurement of impurity line emissions in the Experimental Advanced Superconducting Tokamak

Abstract

A flat-field extreme ultraviolet (EUV) spectrometer working in the 20-500 Å wavelength range with fast time response has been newly developed to measure line emissions from highly ionized tungsten in the Experimental Advanced Superconducting Tokamak (EAST) with a tungsten divertor, while the monitoring of light and medium impurities is also an aim in the present development. A flat-field focal plane for spectral image detection is made by a laminar-type varied-line-spacing concave holographic grating with an angle of incidence of 87°. A back-illuminated charge-coupled device (CCD) with a total size of 26.6 × 6.6 mm{sup 2} and pixel numbers of 1024 × 255 (26 × 26 μm{sup 2}/pixel) is used for recording the focal image of spectral lines. An excellent spectral resolution of Δλ{sub 0} = 3-4 pixels, where Δλ{sub 0} is defined as full width at the foot position of a spectral line, is obtained at the 80-400 Å wavelength range after careful adjustment of the grating and CCD positions. The high signal readout rate of the CCD can improve the temporal resolution of time-resolved spectra when the CCD is operated in the full vertical binning mode. It is usually operated at 5 ms per frame. If the vertical sizemore » of the CCD is reduced with a narrow slit, the time response becomes faster. The high-time response in the spectral measurement therefore makes possible a variety of spectroscopic studies, e.g., impurity behavior in long pulse discharges with edge-localized mode bursts. An absolute intensity calibration of the EUV spectrometer is also carried out with a technique using the EUV bremsstrahlung continuum at 20-150 Å for quantitative data analysis. Thus, the high-time resolution tungsten spectra have been successfully observed with good spectral resolution using the present EUV spectrometer system. Typical tungsten spectra in the EUV wavelength range observed from EAST discharges are presented with absolute intensity and spectral identification.« less

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;  [1]; ; ;  [2];  [3] more »; « less
  1. Institute of Plasma Physics Chinese Academy of Sciences, Hefei 230026, Anhui (China)
  2. National Institute for Fusion Science, Toki 509-5292, Gifu (Japan)
  3. Southwestern Institute of Physics, Chengdu 610041, Sichuan (China)
Publication Date:
OSTI Identifier:
22482644
Resource Type:
Journal Article
Journal Name:
Review of Scientific Instruments
Additional Journal Information:
Journal Volume: 86; Journal Issue: 12; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0034-6748
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CHARGE-COUPLED DEVICES; DATA ANALYSIS; EDGE LOCALIZED MODES; EXTREME ULTRAVIOLET RADIATION; HT-7U TOKAMAK; INCIDENCE ANGLE; PLASMA IMPURITIES; READOUT SYSTEMS; SPECTROMETERS; TIME RESOLUTION; TUNGSTEN

Citation Formats

Zhang, Ling, Xu, Zong, Wu, Zhenwei, Zhang, Pengfei, Wu, Chengrui, Gao, Wei, Shen, Junsong, Chen, Yingjie, Liu, Xiang, Wang, Yumin, Gong, Xianzu, Hu, Liqun, Chen, Junlin, Zhang, Xiaodong, Wan, Baonian, Li, Jiangang, Morita, Shigeru, Ohishi, Tetsutarou, Goto, Motoshi, Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu, Dong, Chunfeng, and others, and. A fast-time-response extreme ultraviolet spectrometer for measurement of impurity line emissions in the Experimental Advanced Superconducting Tokamak. United States: N. p., 2015. Web. doi:10.1063/1.4937723.
Zhang, Ling, Xu, Zong, Wu, Zhenwei, Zhang, Pengfei, Wu, Chengrui, Gao, Wei, Shen, Junsong, Chen, Yingjie, Liu, Xiang, Wang, Yumin, Gong, Xianzu, Hu, Liqun, Chen, Junlin, Zhang, Xiaodong, Wan, Baonian, Li, Jiangang, Morita, Shigeru, Ohishi, Tetsutarou, Goto, Motoshi, Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu, Dong, Chunfeng, & others, and. A fast-time-response extreme ultraviolet spectrometer for measurement of impurity line emissions in the Experimental Advanced Superconducting Tokamak. United States. doi:10.1063/1.4937723.
Zhang, Ling, Xu, Zong, Wu, Zhenwei, Zhang, Pengfei, Wu, Chengrui, Gao, Wei, Shen, Junsong, Chen, Yingjie, Liu, Xiang, Wang, Yumin, Gong, Xianzu, Hu, Liqun, Chen, Junlin, Zhang, Xiaodong, Wan, Baonian, Li, Jiangang, Morita, Shigeru, Ohishi, Tetsutarou, Goto, Motoshi, Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu, Dong, Chunfeng, and others, and. Tue . "A fast-time-response extreme ultraviolet spectrometer for measurement of impurity line emissions in the Experimental Advanced Superconducting Tokamak". United States. doi:10.1063/1.4937723.
@article{osti_22482644,
title = {A fast-time-response extreme ultraviolet spectrometer for measurement of impurity line emissions in the Experimental Advanced Superconducting Tokamak},
author = {Zhang, Ling and Xu, Zong and Wu, Zhenwei and Zhang, Pengfei and Wu, Chengrui and Gao, Wei and Shen, Junsong and Chen, Yingjie and Liu, Xiang and Wang, Yumin and Gong, Xianzu and Hu, Liqun and Chen, Junlin and Zhang, Xiaodong and Wan, Baonian and Li, Jiangang and Morita, Shigeru and Ohishi, Tetsutarou and Goto, Motoshi and Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu and Dong, Chunfeng and others, and},
abstractNote = {A flat-field extreme ultraviolet (EUV) spectrometer working in the 20-500 Å wavelength range with fast time response has been newly developed to measure line emissions from highly ionized tungsten in the Experimental Advanced Superconducting Tokamak (EAST) with a tungsten divertor, while the monitoring of light and medium impurities is also an aim in the present development. A flat-field focal plane for spectral image detection is made by a laminar-type varied-line-spacing concave holographic grating with an angle of incidence of 87°. A back-illuminated charge-coupled device (CCD) with a total size of 26.6 × 6.6 mm{sup 2} and pixel numbers of 1024 × 255 (26 × 26 μm{sup 2}/pixel) is used for recording the focal image of spectral lines. An excellent spectral resolution of Δλ{sub 0} = 3-4 pixels, where Δλ{sub 0} is defined as full width at the foot position of a spectral line, is obtained at the 80-400 Å wavelength range after careful adjustment of the grating and CCD positions. The high signal readout rate of the CCD can improve the temporal resolution of time-resolved spectra when the CCD is operated in the full vertical binning mode. It is usually operated at 5 ms per frame. If the vertical size of the CCD is reduced with a narrow slit, the time response becomes faster. The high-time response in the spectral measurement therefore makes possible a variety of spectroscopic studies, e.g., impurity behavior in long pulse discharges with edge-localized mode bursts. An absolute intensity calibration of the EUV spectrometer is also carried out with a technique using the EUV bremsstrahlung continuum at 20-150 Å for quantitative data analysis. Thus, the high-time resolution tungsten spectra have been successfully observed with good spectral resolution using the present EUV spectrometer system. Typical tungsten spectra in the EUV wavelength range observed from EAST discharges are presented with absolute intensity and spectral identification.},
doi = {10.1063/1.4937723},
journal = {Review of Scientific Instruments},
issn = {0034-6748},
number = 12,
volume = 86,
place = {United States},
year = {2015},
month = {12}
}