Measurement of structure and charge states of swift carbon cluster passing through a thin foil

Chiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa; Adachi, Masahiro; Kaneko, Toshiaki*

The charge states were measured for the constituent ions of 1 MeV/atom C ions passing through a carbon thin foil. The constituent ions of C ions deflected by the deflection plates were detected with a luminance plate position detector monitored by a CCD camera. Since the detected ion signals contain the information of charge states and cluster structure, this measurement method enabled us to investigate the structure-dependent of the average charges in the cluster ions. The data clearly show that the measured average charges of C ions in a linear-chain structure are larger than those in a ring structure. Moreover we found that the edge-position ions in a linear structure have the average charges larger than the middle-position ion. These experimental results are well supported by a recent theory on the cluster average charge.