Spectral profiles of the Hα line emitted from the large helical device plasma [O. Motojima et al., Phys. Plasmas 6, 1843 (1999)] have been measured with polarization-separation optics and a high-resolution spectrometer. Besides the underlying high-temperature component, which probably arises from charge-exchange recombination, the profiles are interpreted as superpositions of Zeeman profiles for two different magnetic field strengths. The emission locations are thus identified on the magnetic field map; the emissions are localized in the inner and outer regions just outside the ergodic layer, and each field-strength contribution to the overall Zeeman profile represents two radiator temperatures, and inward atom flow velocities in the range of (1–7)×103m∕s.

Visible spectral emission lines from magnetic dipole transitions in Ar X, Ar XI, Ar XIV, and Ar XV are observed from plasmas heated with neutral-beam injection ͑NBI͒ in the Large Helical Device ͓O. Motojima et al., Phys. Plasmas 6, 1843 ͑1999͔͒. Orthogonal linearly polarized components of the emission line profiles are observed with a polarization separation optical system and high-resolution spectrometer. Zeeman split profiles reveal polarization characteristics of magnetic dipole transitions. Ion temperatures and emission locations are estimated from the profiles with the magnetic field information on the lines of sight ͑LOS͒. The spatially resolved emissions are observed by the array of absolutely calibrated views. The time histories of line profiles and emission intensities at the poloidal view are presented. The observed line profiles and the intensity distribution at the poloidal view indicate the localization of these charge states in the edge region just inside the last closed flux surface. The emission line of Ar X in the tangential observation indicates Doppler shifts of the Zeeman split profiles. The velocity components of Ar X ion flow along the LOS at the tangential view are 7.7 and 2.0 km/ s at the outer and inner edge plasmas, respectively, in the opposite direction to the NBI.

We have observed motional-Stark-effect (MSE) spectra of the Balmer-α line emitted from a heating neutral-hydrogen beam on the Large Helical Device. The polarization-resolved spectral profile indicates that the magnetic-sublevel populations in the upper level slightly deviate from the statistical distribution, i.e. alignment is created. The theoretical proton-impact cross sections with the assumption of corona equilibrium, however, lead to a profile in gross disagreement with the observed one. It is suggested that the observed profile is the result of time integration of light emission of atoms during the relaxation process, i.e. the aligned population distribution is created by the directional proton collisions and elastic proton collisions destroy the alignment, finally leading to statistical distribution.

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