Spectral profile analysis of the D alpha line in the divertor region of Tore-Supra

The deuterium Palmer line D alpha in Tore-Supra plasmas has been studied ne ar a midplane neutraliser plate (NP) of the ergodic divertor. Line profiles are analysed with a synthetic profile method taking into account Zeeman an d Doppler effects. This analysis shows that two deuterium populations with specific behaviours have to be considered: the first one (cold atoms) is co mposed of atomic deuterium coming from D-2 desorbed from the NP, while the second one (warm atoms) is composed of charge exchange (CX) and reflected D . The Doppler temperature of cold atoms increases with the edge electron de nsity, n(e)(edge) (1.4 eV < T-D(c) < 2.5 eV). Possible causes for this beha viour are analysed; in particular, the possible heating of cold atoms by Df ions is evaluated. On the other hand, the Doppler temperature of warm atom s is not influenced by edge parameter variations (T-D(w) similar to 22 eV). The densities of reflected and CX deuterium atoms are deduced from the exp erimental warm component brightness, coupled to a collisional radiative mod el and to the TRIM code; their values are in satisfactory agreement with th e results of the code EDCOLL. (C) 2001 Elsevier Science B.V. All rights res erved.