Decay of hollow atoms above and below a surface

Abstract

We present some experiments which demonstrate definitively that the filling of the L shell of argon hollow atoms formed below a surface proceeds, like those formed above a surface, through a cascade of eight spontaneous transitions. This result means that the hollow atoms' clock property may be used in both cases to study continuously the approach and penetration of an ion onto a surface as it is experimentally shown. \textcopyright{} 1996 The American Physical Society.