TY - JOUR
T1 - Influence of electron energy distribution on helium recombining plasma diagnostics using line emissions
AU - Takahashi, H.
AU - Okamoto, Atsushi
AU - Kitajima, Sumio
AU - Kobayashi, T.
AU - Boonyarittipong, P.
AU - Miura, T.
AU - Nakamura, D.
AU - Kon, J.
AU - Saikyo, T.
AU - Tanaka, Y.
AU - Goto, M.
N1 - Funding Information:
This research was supported by the Japan Society for the Promotion of Science (JSPS), 26420848; 17K14895.
Publisher Copyright:
© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
PY - 2017/9
Y1 - 2017/9
N2 - The influence of electron energy distribution on helium recombining plasma diagnostics is investigated using a helium collisional-radiative model. The population densities of excited helium atoms are calculated for Maxwellian and non-Maxwellian distribution plasma cases. In the case of the Maxwellian distribution plasma, the electron temperature and electron density determined by the Boltzmann plot method agree well with the input plasma parameters. On the other hand, it is indicated that the electron temperature and electron density are significantly underestimated in the bi-Maxwellian distribution plasma case, even though the density of the hot electron components is three orders smaller than that of the bulk electrons. This result indicates that in a non-Maxwellian helium recombining plasma, evaluation of the particle balance based on line emissions from excited helium atoms would be difficult because the reaction rate of atomic and molecular processes is strongly dependent on the electron temperature and density.
AB - The influence of electron energy distribution on helium recombining plasma diagnostics is investigated using a helium collisional-radiative model. The population densities of excited helium atoms are calculated for Maxwellian and non-Maxwellian distribution plasma cases. In the case of the Maxwellian distribution plasma, the electron temperature and electron density determined by the Boltzmann plot method agree well with the input plasma parameters. On the other hand, it is indicated that the electron temperature and electron density are significantly underestimated in the bi-Maxwellian distribution plasma case, even though the density of the hot electron components is three orders smaller than that of the bulk electrons. This result indicates that in a non-Maxwellian helium recombining plasma, evaluation of the particle balance based on line emissions from excited helium atoms would be difficult because the reaction rate of atomic and molecular processes is strongly dependent on the electron temperature and density.
KW - Boltzmann plot method
KW - divertor
KW - electron energy distribution
KW - helium collisional-radiative model
KW - volumetric recombination
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U2 - 10.1002/ctpp.201700014
DO - 10.1002/ctpp.201700014
M3 - Article
AN - SCOPUS:85029227457
VL - 57
SP - 322
EP - 328
JO - Contributions to Plasma Physics
JF - Contributions to Plasma Physics
SN - 0863-1042
IS - 8
ER -