Fusion ofSi28+Si28

The energy dependence of the fusion cross section for ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ + ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ has been studied over the bombarding energy range 80-140 MeV. The gross features of these cross sections are compared with the expectations of entrance channel models and with the results of time-dependent Hartree Fock calculations. A comparison with similar data for the ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$ + ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ + ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ systems gives results which are not inconsistent with a compound nucleus limitation to fusion at high energies. A search for fusion oscillations similar to those found in lighter systems provides some evidence for their occurrence in the ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ + ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ system.