Selective Electron Capture: A Dominant Production Process for Few-Electron States of Light Target Atoms after Heavy-Ion Impact

The total and delayed $K$-Auger-electron emission of Ne, ${\mathrm{N}}_2$, and S${\mathrm{F}}_6$ targets was investigated after 1.4-MeV/u ${\mathrm{Kr}}^{18+}$ and ${\mathrm{Ar}}^{12+}$ impact. The lines of promptly decaying $1s2ln{l}^{\prime } (n>~3)$ states observed nanoseconds after projectile impact demonstrate that selective electron capture from neutral target atoms into outer-shell orbitals of slow recoils is an important production mechanism for certain states in highly stripped target atoms. Contributions of prompt and delayed excited states are observed as well as specific cascades to inner-shell states.