Image acceleration of highly charged ions by metal surfaces

Abstract

We present classical simulations for the energy gain, \ensuremath{\Delta}E, due to the image acceleration of very highly charged ions (Q\ensuremath{\gg}10) by metal surfaces. We show that for large Q the simulated values \ensuremath{\Delta}E, based on the classical over-barrier model, fall below the ``staircase'' model but still exceed the lower bound for classically allowed transitions. The results are in reasonable agreement with recent experimental data. Effects of the nonzero velocity of the projectile parallel to the surface appear to be insignificant for the energy gain. \textcopyright{} 1996 The American Physical Society.