Magnetic Axial Dependency of Hα Emission Location in Peripheral Plasmas of Large Helical Device as Determined by Plasma Polarization Spectroscopy

Atsushi IWAMAE; Atsushi SAKAUE; Nobuhiro NESHI; Jun YANAGIBAYASHI; Masahiro HASUO; Daisuke NAKAMURA; Keiji SAWADA; Motoshi GOTO; Shigeru MORITA

doi:10.1585/pfr.5.032

Regular Articles

Magnetic Axial Dependency of Hα Emission Location in Peripheral Plasmas of Large Helical Device as Determined by Plasma Polarization Spectroscopy

Atsushi IWAMAE, Atsushi SAKAUE, Nobuhiro NESHI, Jun YANAGIBAYASHI, Masahiro HASUO, Daisuke NAKAMURA, Keiji SAWADA, Motoshi GOTO, Shigeru MORITA

Author information

Atsushi IWAMAE
Department of Mechanical Engineering and Science Kyoto University, Kyoto 606-8501, Japan
Atsushi SAKAUE
Department of Mechanical Engineering and Science Kyoto University, Kyoto 606-8501, Japan
Nobuhiro NESHI
Department of Mechanical Engineering and Science Kyoto University, Kyoto 606-8501, Japan
Jun YANAGIBAYASHI
Department of Mechanical Engineering and Science Kyoto University, Kyoto 606-8501, Japan
Masahiro HASUO
Department of Mechanical Engineering and Science Kyoto University, Kyoto 606-8501, Japan
Daisuke NAKAMURA
Faculty of Engineering, Shinshu University, Wakasato, Nagano 380-8553, Japan
Keiji SAWADA
Faculty of Engineering, Shinshu University, Wakasato, Nagano 380-8553, Japan
Motoshi GOTO
National Institute for Fusion Science, Toki, Gifu 509-5292, Japan
Shigeru MORITA
National Institute for Fusion Science, Toki, Gifu 509-5292, Japan

Keywords: hydrogen Balmer α, polarization, neutral particle transport, spectral line profile, peripheral plasma

JOURNAL FREE ACCESS

2010 Volume 5 Pages 032

DOI https://doi.org/10.1585/pfr.5.032

Details

Abstract

The behavior of hydrogen neutral particles in and around the ergodic layer of Large Helical Device plasmas has been investigated through Hα emission spectral line profiles using plasma polarization spectroscopy (PPS). The PPS technique enables us to quantitatively evaluate emission locations, atomic temperatures and velocity components along the line-of-sight (LOS) for both inner and outer peripheral regions. The emission locations and the LOS components of atomic velocities are determined by varying the magnetic field axis R_ax from 3.60 m to 4.00 m, shot by shot. The high intensity region of Hα emissions is localized in the inner ergodic layer for the inward configuration. With an increase in R_ax, the high intensity region of Hα emission moves outward.

Corresponding author

Register with J-STAGE for free!