TY - JOUR
T1 - Space-resolving VUV and soft X-ray spectroscopy in the tandem mirror gamma 10 plasma
AU - Yoshikawa, M.
AU - Okamoto, Y.
AU - Kawamori, E.
AU - Watanabe, Y.
AU - Watabe, C.
AU - Furukawa, T.
AU - Kubota, Y.
AU - Sedo, K.
AU - Cho, T.
AU - Yatsu, K.
AU - Yamaguchi, N.
N1 - Funding Information:
The authors would like to thank the members of the GAMMA 10 group of the University of Tsukuba for their collaboration. Part of this work was supported by a University of Tsukuba Project Research Fund. Part of the work has been performed under the approval of the Photon Factory Advisory Committee.
PY - 2002/2
Y1 - 2002/2
N2 - Vacuum ultraviolet (VUV) and soft X-ray (SX) spectroscopic measurements are important means to diagnose radiation power loss, impurity ion densities and effective charge of confined plasma, Zeff, in magnetically confined plasmas such as fusion plasmas. We have constructed space- and time-resolving flat-field VUV (150-1050 Å) and SX (20-350 Å) spectrographs by using aberration-corrected concave gratings with varied line spacing. Absolute calibration experiments have been conducted at the Photon Factory in the High Energy Accelerator Research Organization. Absolute sensitivities of the VUV and SX spectrographs have been obtained for the two (S and P) polarization geometries. Thus, absolute intensities of emission spectra from impurity ions can be measured together with their radial distributions in plasmas. The total radiation power was determined to be less than 6 kW within ±20% of error in our normal plasma operation. Density profiles of impurity ions were reduced by using absolute emissivities of impurity lines and a collisional-radiative model. Moreover, the value of Zeff is estimated to be 1.00 in the tandem mirror GAMMA 10 plasma.
AB - Vacuum ultraviolet (VUV) and soft X-ray (SX) spectroscopic measurements are important means to diagnose radiation power loss, impurity ion densities and effective charge of confined plasma, Zeff, in magnetically confined plasmas such as fusion plasmas. We have constructed space- and time-resolving flat-field VUV (150-1050 Å) and SX (20-350 Å) spectrographs by using aberration-corrected concave gratings with varied line spacing. Absolute calibration experiments have been conducted at the Photon Factory in the High Energy Accelerator Research Organization. Absolute sensitivities of the VUV and SX spectrographs have been obtained for the two (S and P) polarization geometries. Thus, absolute intensities of emission spectra from impurity ions can be measured together with their radial distributions in plasmas. The total radiation power was determined to be less than 6 kW within ±20% of error in our normal plasma operation. Density profiles of impurity ions were reduced by using absolute emissivities of impurity lines and a collisional-radiative model. Moreover, the value of Zeff is estimated to be 1.00 in the tandem mirror GAMMA 10 plasma.
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U2 - 10.1142/S0218625X02002634
DO - 10.1142/S0218625X02002634
M3 - Article
AN - SCOPUS:0036462898
SN - 0218-625X
VL - 9
SP - 555
EP - 559
JO - Surface Review and Letters
JF - Surface Review and Letters
IS - 1
ER -