Proton-Induced Fine-Structure Transitions

Experimental studies of the intensity of the (2pl/2-lsl/2) and (2p3/2-lsl/2) lines of SXVI in the Alcator Takamak show large departures from the statistical ratio of 0.5 (Källne et al. 1982). Similar enhancements in the intensity ratio have been reported in solar observations (Grineva et al. 1973, Phillips et al. 1982) for the Mg XII lines and in laser produced plasmas (Boiko et al. 1977). Theoretical calculations of the intensity ratio have been carried out by Vinogradov et al. (1977), Beigman et al. (1979) and Ljepojevic et al. (1984) . We suspect that proton-impact induced transitions play a crucial role which depends sensitively on the conditions of temperature and density in the Plasma. In this abstract we will present some preliminary results of proton-impact excitation cross section calculations, for the n=2 sub levels of hydrogenic ions.