The interaction of ${\mathrm{Ar}}^{\mathrm{}(17,18)+}$ ions with ${\mathrm{C}}_{60}$ has been studied by observing coincidences between Ar $K$ x rays and the fullerene ions and fragments. At large distances the capture of electrons from ${\mathrm{C}}_{60}$ into excited states of the ion has been observed and compared to the interaction of the same ions with surfaces. Most of the observed events correspond to the capture of many electrons by the ion and the loss of all but one. These results show clearly the characteristic behavior of ions flying over a surface without any contact.

• Received 19 December 1995

DOI:https://doi.org/10.1103/PhysRevA.53.R2925