EXCITATION AND FRAGMENTATION OF HIGHLY-CHARGED METAL-CLUSTERS IN COLLISIONS WITH IONS

We discuss the Coulomb fragmentation of highly charged metal clusters. The analogy with a classical conducting liquid drop is assessed from molecular dynamics calculations. Experimentally, the highly charged me tal clusters are formed in collisions with highly charged ions (Xe20+, Ar11+, Ar8+, Ar3+, and O5+) at low velocity. We show new experimental data on the rate of emitted light charged particles that indicate an as yet unobserved fragmentation regime. Collisions of ions with metal clusters also offer a unique method to strongly excite the conducting electron gas within a short time of a few fs opening the possibility t o study large amplitude electron dynamics and relaxation in microscopi c systems.