Electron emission from surfaces bombarded by MeV atom clusters

Pronounced suppression of electron emission from surfaces bombarded by fast clusters is one of the well-known vicinage effects. However, the main mechanism of the suppression still remains unsolved. In this paper, recent electron spectroscopy studies of the vicinage effect at Tsukuba are reviewed with emphasis on the suppression mechanism of the electron emission in the transport stage. We discuss that the interference of wake potentials generated by the cluster atoms is effective to disturb the electron transport. This mechanism reasonably accounts for the observed suppression of electron emission.