Identification of distinct two-electron transfer processes in collisions

KVI, Atomic Physics, Rijksuniversiteit Groningen - Zernikelaan 25 NL-9747 AA Groningen, The Netherlands

Corresponding author: hoekstra@kvi.nl

Received: 10 March 2006
Accepted: 24 April 2006

Abstract

Two-electron capture in 7.5 collisions is investigated by measuring the momenta of the recoil ions. The Q-value spectrum shows two groups of two-electron capture channels, namely and (). The manifolds in between, and , are barely populated. The population of the () states occurs via two consecutive one-electron transitions, while transfer to the channels occurs at a direct crossing with the entrance channel. These findings show that for capturing two non-equivalent electrons the population of symmetric and asymmetric nln'l' projectile states can also be described by dielectronic and monoelectronic transitions, respectively, just as for the capture of two equivalent electrons from noble gasses. However, the population mechanisms are the other way round.