We have used the asymmetric two-center shell model to calculate the single-neutron energies in the ${}_{}{}^{12}{}_{}{}^{}$C${+\mathrm{}}^{17}$,18O and ${}_{}{}^{13}{}_{}{}^{}$C${+\mathrm{}}^{17}$O collisions as a function of the internuclear distance. The periodic resonancelike structures observed in the angle-integrated inelastic cross sections for these systems can be understood in terms of the nuclear Landau-Zener promotion of a loosely bound valence neutron from the 1$d_{5/2}$ (Ω=(1/2) state to the 2$s_{1/2}$ state of the oxygen isotopes. Inclusion of the effects of a turning point in the Landau-Zener formula is found to give marked improvements in accounting for the observed angle-integrated inelastic cross sections for these systems. Intermediate structures in the cross sections are found to arise due to the energy-dependent oscillatory behavior of the partial cross sections. While some resonancelike peaks can be attributed to a single orbital angular momentum, many others arise due to the combined contributions of two or more angular momenta.

• Received 22 July 1987

DOI:https://doi.org/10.1103/PhysRevC.36.2341