Two-Electron-One-Photon Transitions in Heavy-Ion Collisions

Abstract

Heavy-ion-atom collisions at medium energies (\ensuremath{\sim}0.8 MeV/amu) yield a considerable probability for multiple inner-shell ionization. In the Ni-Ni, Ni-Fe, Fe-Ni, and Fe-Fe cases, distinct lines in the x-ray spectra are observed, which must be interpreted as a correlated two-electron jump into the doubly ionized $K$ shell followed by the emission of only one photon carrying away the total transition energy.