Search for structure in the fusion ofO16+Ca40

The fusion of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ + ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ has been studied in small energy steps in the energy range $45\le E_{\mathrm{lab}}\le 63$ MeV. Fusion cross sections were measured by the detection of evaporation residues in a $\Delta E-E$ particle telescope and by measurement of prompt $\gamma$-ray activity. The fusion excitation functions show relatively smooth behavior with no evidence for oscillatory structure of the magnitude observed in the fusion of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ + ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$.