1. The interaction of an energetic ion colliding with condensed matter, resulting in an elastic or inelastic ion colliding with condensed matter, resulting in elastic or inelastic scattering of the ions, the release of atoms from the target, emission of photons, ionization of target atoms, or ion implantations.
2. An atomic process that occurs as a result of the collision of energetic ions, atoms, or molecules with condensed matter.