Vibrational populations of N2(B 3IIsub(g)) and CO(a 3II) produced by He+ impact on N2(X) and CO(X) in the 200-1000 eV energy range

High-resolution energy loss spectra (ELS) for the production of N2(B 3IIsub(g)) and CO(a 3II) in collisions of He+ on N2(X 1Σ+sub(g)) and CO(X 1Σ+) have been obtained in the 200 eV <= E <= 1 keV energy range. The measured vibrational distributions show a non-Franck-Condon (FC) behaviour for E < 500 eV in the case of N2. In the case of CO, deviations from FC distributions are found in the entire energy range. For E < 500 eV the deviations from FC distributions in both the N2 and CO cases are tentatively attributed to perturbations caused by near-resonant charge exchange channels. (author)