Investigation of double capture in Ne8++He, H2, by electron spectroscopy at 80 keV. II. Experimental results

Abstract

For pt.I see ibid., vol.24, no.7, p.1695-72 (1991). A thorough analysis of electron spectra measured at 80 keV in collisions between Ne8+(1s2) ions and helium and molecular hydrogen targets is presented. The 1s23lnl' and 1s24lnl' lines are identified up to n=9. With helium, a fitting procedure for 1s23lnl' lines (all the lines for n=3, 4, and the first 3s5l ones), observed for the first time at different angles, make it possible to compare the authors' experimental results with two different theoretical data sets: their own theoretical values for positions, autoionization and radiative probabilities obtained by the AUTOLSJ method, which are given in a companion paper, and those recently published by Bachau et al. using a Feshbach method with a model potential. This allows the authors to test both theoretical positions and lifetimes of (3,n) states. The relative weight of the n=3, 4 and the first n=5 states is often angle dependent. The apparent, angle dependent, branching ratio for autoionization into the 2p and 2s continua of the (3,3) and the first (3,4) states is determined for several cases and discussed. Finally, differential and total cross sections are given and compared with other available experimental results.