Angular distribution of Auger electron emission following double electron capture in 90-keV C 6+ + He collisions

Abstract

Angular distributions of K-Auger-electrons ejected in 90-keV C 6+ +He collisions were measured to determine cross sections for the production of the configurations 2 lnl′ ( n ⩾ 3). Previous cross sections obtained assuming isotropic Auger distributions were verified. For n=5 and 6 the angular distributions were confirmed to be isotropic within the experimental uncertainties whereas anisotropic electron emission was observed for n=3 and 4. The data yield revised cross sections which are in good agreement with theoretical calculations from Harel et al. The analysis of individual terms 2 l3 l′ 1L shows that the anisotropy is due to the highest angular momenta, and M=0 substates are preferentially populated.