Hydrogen Atomic and Molecular Emission Locations and Intensities in the LHD Edge Plasma Determined from Simultaneously Observed Polarization Spectra

Keisuke Fujii, Keiji Sawada, Motoshi Goto, Shigeru Morita, Masahiro Hasuo

Research output: Contribution to journalArticlepeer-review

1 Scopus citations

Abstract

We observed polarization-resolved emission spectra of the Balmer-α, -β, and -γ lines of hydrogen atoms and the Q branches of the Fulcher-α band of hydrogen molecules simultaneously with six lines of sight in a poloidal cross section of the Large Helical Device (LHD). From the fit of the spectra including the line splits and their polarization dependence due to the Zeeman effect, we determined the emission locations, intensities and temperatures of the atoms and molecules. The determined emission locations of the hydrogen atoms were just outside the last closed flux surface and the intensities showed small dependence on the location. The emission locations of the molecules were rather around the divertor legs and their emission intensities showed location dependences. The determined atomic temperature was about 1 eV and the molecular rotational temperature was 0.04-0.07 eV, both of which showed no systematic dependence on the location within the experimental accuracy.

Original languageEnglish
Pages (from-to)1-5
Number of pages5
JournalPlasma and Fusion Research
Volume10
DOIs
StatePublished - 2015
Externally publishedYes

Funding

The authors are grateful to the LHD experimental group for their support. This work was supported by the National Institute for Fusion Science (Grant No. NIFS08KOAP020, NIFS10KLMP003).

Keywords

  • Balmer emission spectra
  • Emission locations and intensities
  • Fulcher-α emission spectra
  • LHD edge plasma
  • Polarization spectroscopy
  • Zeeman effect

Fingerprint

Dive into the research topics of 'Hydrogen Atomic and Molecular Emission Locations and Intensities in the LHD Edge Plasma Determined from Simultaneously Observed Polarization Spectra'. Together they form a unique fingerprint.

Cite this