Electron detachment in Li--He collisions: coherence study of Li(22P) excitation in Li--He and Li-He collisions
- 28 February 1989
- journal article
- Published by IOP Publishing in Journal of Physics B: Atomic, Molecular and Optical Physics
- Vol. 22 (4) , 617-626
- https://doi.org/10.1088/0953-4075/22/4/008
Abstract
Electron detachment in Li--He collisions in the 1-20 keV amu-1 energy range has recently been studied theoretically by Vu Ngoc Tuan and Gauyacq (1987), using an 'independent-scattering model'. A detailed test of the independent-scattering model has been carried out by studying the orientation and alignment of the Li(22P) states created in 2-25 keV Li-He and 3-12 keV Li--He collisions, using the polarised photon-scattered particle coincidence technique. In the region of maximum excitation probability, a strong preference for population of Li(2p-1) is observed for both types of collisions, supporting the independent-scattering model for Li--He collisions. The degrees of polarisation are, however, different for the two collision processes. Correlation between the two outer electrons in Li- may account for the different polarisations. The scaling law for H-, Li-, Na-, K- destruction cross sections, which initiated this study, is discussed.Keywords
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