Trajectory-dependent highly charged ion-induced electron yield from single-layer graphene

Abstract We study the neutralisation dynamics of highly charged ions by transmission through a free-standing single layer of graphene in dependence of the particle trajectory. Both the secondary electron yield and the neutralisation of the ion increase for increasing scattering angles (smaller impact parameters). This supports the current understanding of highly charged ion deexcitation, according to which the presence of an interatomic deexcitation mechanism with improved efficiency in the proximity of neighbours is necessary in addition to intraatomic radiative- and non-radiative decay pathways.