论文信息 - Magnetic depolarisation studies on the polarisation of He I lines impact excited by 10-35 keV Ne+ ions

Magnetic depolarisation studies on the polarisation of He I lines impact excited by 10-35 keV Ne+ ions

The polarisation of the 492 (1s4d1D to 1s2p1P) and 668 nm (1s3d1D to 1s2p1P) fluorescence lines of He I impact excited by 10-35 keV Ne+ ions has been investigated. Using magnetic depolarisation techniques, the contribution of cascade processes to the polarisation fraction could be separated. For both spectral lines the authors find a strong but approximately energy-independent cascade contribution to the polarisation fraction. Therefore the significant energy dependence of the total polarisation fraction reflects mainly an energy dependence of the direct excitation process. This result confirms the lack of correlation between emission cross sections and polarisation data of He I lines previously observed by Andersen et al. (1977) for Ne+-He collisions.

G. Oppen | D. Szostak | W. Perschmann | A. S. Ayunacioglu

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