| High resolution x-ray spectroscopy has been used to measure the cross sections for forming doubly excited F('7+) ions in the 2s2p and 2p('2) configurations following a F('8+) + He, Ne, or Ar collision over the projectile energy range of 13 to 31 MeV. The intermediate states are found to be formed by projectile electron excitation coupled with target to projectile electron transfer to an excited state during a single ion-atom collision. This process is termed nonresonant transfer excitation. A competing process for formation of the doubly excited states observed is resonant transfer excitation, a process postulated to be analogus to dielectronic recombination. Although the projectile energies spanned the region where resonant transfer excitation is expected to maximize, no contribution to the measured cross sections was observed. |
