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Title: Absolute calibration of vacuum ultraviolet spectrograph system for plasma diagnostics

Abstract

A space- and time-resolving vacuum ultraviolet (VUV) spectrograph system has been applied to diagnose impurity ions behavior in plasmas produced in the tandem mirror GAMMA 10 and the reversed field pinch TPE-RX. We have carried out ray tracing calculations for obtaining the characteristics of the VUV spectrograph and calibration experiments to measure the absolute sensitivities of the VUV spectrograph system for the wavelength range from 100 to 1100 A. By changing the incident angle, 50.6 deg. -51.4 deg., to the spectrograph whose nominal incident angle is 51 deg., we can change the observing spectral range of the VUV spectrograph. In this article, we show the ray tracing calculation results and absolute sensitivities when the angle of incidence into the VUV spectrograph is changed, and the results of VUV spectroscopic measurement in both GAMMA 10 and TPE-RX plasmas.

Authors:
; ; ; ; ; ; ; ; ;  [1];  [2];  [2]
  1. Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan)
  2. (Japan)
Publication Date:
OSTI Identifier:
20641238
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 75; Journal Issue: 10; Conference: 15. topical conference on high temperature plasma diagnostics, San Diego, CA (United States), 19-22 Apr 2004; Other Information: DOI: 10.1063/1.1789264; (c) 2004 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CALIBRATION; FAR ULTRAVIOLET RADIATION; GAMMA 10 DEVICES; INCIDENCE ANGLE; PLASMA DIAGNOSTICS; PLASMA IMPURITIES; REVERSE-FIELD PINCH; SENSITIVITY; TPE-RX DEVICE; ULTRAVIOLET SPECTROMETERS; WAVELENGTHS

Citation Formats

Yoshikawa, M., Kubota, Y., Kobayashi, T., Saito, M., Numada, N., Nakashima, Y., Cho, T., Koguchi, H., Yagi, Y., Yamaguchi, N., National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, and Toyota Technological Institute, Tempaku, Nagoya, Aichi 468-8511. Absolute calibration of vacuum ultraviolet spectrograph system for plasma diagnostics. United States: N. p., 2004. Web. doi:10.1063/1.1789264.
Yoshikawa, M., Kubota, Y., Kobayashi, T., Saito, M., Numada, N., Nakashima, Y., Cho, T., Koguchi, H., Yagi, Y., Yamaguchi, N., National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, & Toyota Technological Institute, Tempaku, Nagoya, Aichi 468-8511. Absolute calibration of vacuum ultraviolet spectrograph system for plasma diagnostics. United States. doi:10.1063/1.1789264.
Yoshikawa, M., Kubota, Y., Kobayashi, T., Saito, M., Numada, N., Nakashima, Y., Cho, T., Koguchi, H., Yagi, Y., Yamaguchi, N., National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, and Toyota Technological Institute, Tempaku, Nagoya, Aichi 468-8511. Fri . "Absolute calibration of vacuum ultraviolet spectrograph system for plasma diagnostics". United States. doi:10.1063/1.1789264.
@article{osti_20641238,
title = {Absolute calibration of vacuum ultraviolet spectrograph system for plasma diagnostics},
author = {Yoshikawa, M. and Kubota, Y. and Kobayashi, T. and Saito, M. and Numada, N. and Nakashima, Y. and Cho, T. and Koguchi, H. and Yagi, Y. and Yamaguchi, N. and National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568 and Toyota Technological Institute, Tempaku, Nagoya, Aichi 468-8511},
abstractNote = {A space- and time-resolving vacuum ultraviolet (VUV) spectrograph system has been applied to diagnose impurity ions behavior in plasmas produced in the tandem mirror GAMMA 10 and the reversed field pinch TPE-RX. We have carried out ray tracing calculations for obtaining the characteristics of the VUV spectrograph and calibration experiments to measure the absolute sensitivities of the VUV spectrograph system for the wavelength range from 100 to 1100 A. By changing the incident angle, 50.6 deg. -51.4 deg., to the spectrograph whose nominal incident angle is 51 deg., we can change the observing spectral range of the VUV spectrograph. In this article, we show the ray tracing calculation results and absolute sensitivities when the angle of incidence into the VUV spectrograph is changed, and the results of VUV spectroscopic measurement in both GAMMA 10 and TPE-RX plasmas.},
doi = {10.1063/1.1789264},
journal = {Review of Scientific Instruments},
number = 10,
volume = 75,
place = {United States},
year = {Fri Oct 01 00:00:00 EDT 2004},
month = {Fri Oct 01 00:00:00 EDT 2004}
}
  • A high throughput, shielded, multichannel, extreme ultraviolet (XUV) spectrograph to be used for plasma diagnostics was built. The instrument uses seven hollow fibers to transport the radiation by multiple grazing incidence reflections from the tokamak port through the instrument's shield to the spectrometer entrance slit. In this way, the ratio of background radiation streaming through the entrance slit to XUV flux is reduced by a factor of at least 2500. The seven hollow fibers provide seven channels corresponding to seven different lines of sight through the plasma. The spectrograph uses a toroidal mirror together with a plane, aberration-corrected grating tomore » disperse radiation in the 50--200 A region. Up to seven spectra are recorded simultaneously, at rates of 30--90 Hz, using a microchannel plate assembly optically coupled to a charge-coupled device camera. This will permit, during a single discharge, measurement of spatial emissivity profiles from various ionization states of an injected impurity, providing a better understanding of their time evolution and valuable information on cross-field ion transport.« less
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