Excited States of Few-Electron Recoil Ions from Ion Impact on Neon Studied by X-Ray and Electron Measurements

Neon K Auger-electron and X-ray spectra have been measured for various incident ions (Cl to U) and for different velocities (0.3-9 MeV amu -1 ). The degree of ionization of the L shell increases with increasing charge of the ion and decreases with increasing velocity, and it is represented as function of the projectile velocity divided by charge. Electron capture into metastable, highly charged neon recoil atoms proceeds in a highly selective way to specific states, which are studied by measuring delayed emission from gas mixtures. Delayed neon X-ray spectra induced by 0.6-0.7 MeV amu -1 Cl 10+ are presented. A classical model, using the ionization potential for the captured electron and the subshell specific binding energy in highly charged ions, explains the Rydberg state and estimates the cross section for the observed electron capture.