Computer simulation of above-surface neutralization of highly charged ions approaching a metal surface

Neutralization of highly charged ions at their approaching a metal surface is investigated using the Monte-Carlo method. The electron exchange processes between highly charged ions and the conduction band of metal are considered within the framework of the classical overbarrier model. The results of calculations of neutralization of Ar(10+18)+ on Au surface have shown that a significant part of neutralization energy can be transferred to electrons of the conduction band via both resonant loss of electrons into empty states of the conduction band and emission of captured electrons into vacuum by the promotion mechanism. As a result of the losing of most of the captured electrons over these channels, the highly charged ions approach the surface still being in charged states. (C) 1999 Elsevier Science B.V. All rights reserved.