FAST-ELECTRON EMISSION IN COLLISIONS OF IONS WITH METAL-CLUSTERS

We present a model to describe the dynamical evolution of the delocali zed electrons in a simple metal cluster during and following the passa ge of a charged particle at intermediate energies. Assuming a mean-fie ld approximation we solve the Vlasov equation by combining the test-pa rticle method and the numerical resolution of the Poisson equation at each time step. This method allows one to use a large number of test p articles and to obtain a reliable behavior of the one-body phase-space density over more than 20 fs. The rate and features of fast electron emission are predicted.