Extraction of MeV high energy cluster beams using tandem accelerator

Small cluster ions such as Bn+ (n = 2), Cn+ (n < 10), Sin+(n 2,3,4) and Aun+ (n = 2) have been accelerated to 1-4 MeV in the 3 x 2 MV tandem pelletron of Fudan University (NEC 9SDH2). Intensities of the MeV cluster beams ranging from 0.1 to 100 nA depend on the type of cluster ions and the number of atom it contains. The low energy negative cluster ions injected were obtained from a cesium sputter source (SNICS II). The mass analysis of the high energy cluster beams was performed by a switching magnet. The mass spectrum of the carbon cluster beam produced in the collisions of C8- cluster ions with stripping gas molecules N2 indicates that there is an odd-even effect related to the carbon cluster structure