Quantitative evaluation of charge state for internuclear distance of constituent ions dissociated from C ion moving in a solid

Chiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Yamada, Keisuke; Kaneko, Toshiaki*

An average charge of the constituent ions resulting from the foil-induced dissociation of cluster ions is smaller than that of monatomic ions at the same speed. It is considered that such a charge reduction effect in cluster ion bombardments depend strongly on the internuclear distance between constituent ions moving in a solid. However, there are few reports in which average charges of the constituent ions had been quantitatively evaluated in terms of their internuclear distance increasing by the screened Coulomb repulsion. Therefore, we developed a method which evaluate quantitatively the average charge for internuclear distance of constituent ions in solid through the measurements of the divergence angle of the constituent ions after foil penetration. The achieved results are approximately equal to the theoretical value derived from model considering the cluster effect in average charge.