- Conference date: 3-7 June 2002
- Location: Berkeley, California (USA)
Zeeman spectroscopy is a valuable tool both for diagnostic purposes, and for more fundamental studies of atomic and molecular processes in the boundary region of magnetically confined fusion plasmas (B ≃ 1 to 10 T). The method works well when the Zeeman (Paschen‐Back) effect plays an important, or dominant, rôle in relation to other broadening mechanisms (Doppler, Stark, resonant excitation transfer) in determining the spectral line shape. For impurity species identification and temperature determination, Zeeman spectroscopy has advantages over charge‐exchange recombination spectroscopy from highly excited radiator states, since spectral features practically unique to the species under investigation are analysed. It also provides useful information on probable mechanisms of line production (e.g. sputtering mechanisms, electron impact‐induced dissociative excitation from molecules in the edge plasma), and on the temperature evolution of lower charge states in the process of convection inwards or diffusion outwards from the hotter plasma interior. Where different physical processes are responsible for different sections of the line profile — especially in the case of hydrogen isotopes — Zeeman spectroscopy can provide a set of characteristic temperatures for each section. The method is introduced in both passive and active spectroscopy, and general principles of the Zeeman effect are discussed with special reference to régimes of interest for the tokamak. Relevant physical processes (sputtering mechanisms, electron impact‐induced dissociative excitation from molecules in the edge plasma, and ion‐atom collisional heating mechanisms) are illustrated by sample spectra.
- Zeeman effect
- Electron spectroscopy
- Plasma convection
- Plasma temperature
- Astronomical spectroscopy
Y. K. Semertzidis, M. Aoki, M. Auzinsh, V. Balakin, A. Bazhan, G. W. Bennett, R. M. Carey, P. Cushman, P. T. Debevec, A. Dudnikov, F. J. M. Farley, D. W. Hertzog, M. Iwasaki, K. Jungmann, D. Kawall, B. Khazin, I. B. Khriplovich, B. Kirk, Y. Kuno, D. M. Lazarus, L. B. Leipuner, V. Logashenko, K. R. Lynch, W. J. Marciano, R. McNabb, W. Meng, J. P. Miller, W. M. Morse, C. J. G. Onderwater, Y. F. Orlov, C. S. Ozben, R. Prigl, S. Rescia, B. L. Roberts, N. Shafer‐Ray, A. Silenko, E. J. Stephenson, K. Yoshimura and EDM Collaboration
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