Oscillations in the Excitation Function for Complete Fusion ofO16+C12

The total fusion cross section for the ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$+${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ system has been measured in the ranges $13 \mathrm{MeV}<~E_{\mathrm{c}.\mathrm{m}.\mathrm{}}<~27 \mathrm{MeV}$. The cross section is found to increase with bombarding energy up to $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}\approx 17$ MeV but to stay roughly constant at higher energies, in qualitative agreement with predictions of current models. Superimposed on this average cross-section behavior we observe unexpected oscillations with a period of about 3-4 MeV (c.m. energy).