Reaction cross sections forO16+O16

The total fusion cross section ${\sigma }_f$ for ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ + ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ has been measured in 500 keV steps between 12.5 and 30.5 MeV c.m. energy via $\gamma$-ray techniques. The excitation function for ${\sigma }_f$ shows clear evidence of periodic structure between 14 and 28 MeV (c.m.), as predicted by the optical model. These oscillations are out of phase with those observed in 90° elastic scattering. Individual yields of 12 nuclides formed in the reaction were also obtained. The narrow ($\Gamma <1\mathrm{}$ MeV) resonance at $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=26.5\mathrm{}$ MeV, which is correlated in the ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ ($3^{-}$) channels, is suggested to be an "α-exchange" resonance.