Doppler broadening and magnetic field effects on some ion impurity spectra emitted in the boundary layer of a tokamak plasmaFunded under: FP3-FUSION 11C
Examples are presented of Doppler broadening measurements on singlet, doublet and triplet emission spectra from the following impurity ions found in the boundary layer of the TEXTOR tokamak: C(II), C(III), C(IV), Si(II) and Si(III). The shapes of these spectral lines are significantly influenced by the confining magnetic field of some 2T, in some cases exhibiting an appreciable Paschen-Back effect which complicates their appearance. The particular ion temperature can be obtained from the Doppler widths of the various Zeeman components. Such temperatures derived from partially ionised impurity species should, however, be cautiously interpreted, as the ions in question probably do not exist for long enough in the particular ionisation stage to achieve thermal equilibrium with the background deuterons and protons. This interpretation is supported by a simple one-dimensional model of ionisation and collisional heating processes in the plasma boundary.
Bibliographic Reference: Article: Contributions to Plasma Physics, Vol. 34 (1994) No. 6, pp. 725-747
Record Number: 199510231 / Last updated on: 1995-02-21
Original language: en
Available languages: en