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Slow highly charged ions approaching surfaces at very close distances (∼nm) are known to capture many electrons in highly excited states forming hollow atoms(1)(2). These hollow atoms quickly decay to their ground states through a long cascade of autoionization processes( Auger transitions) which may be balanced , as these ions are still close to the surface, by a series of electron captures. This actual sequence of many events of capture and autoionization, alternate or not, is not experimentally known to date, and depends on the charge of the ions and of the capture processes which may be very different above metals and insulators. We review in this paper two new experiments on the kinematics of fully decelerated highly charged ions(Ar18+) above dielectric and metal surfaces, and on the behavior of ions of lower charge states (O7+ and Ne9+) above the same surfaces. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]