Spin distributions at the Coulomb barrier in the 58Ni+60Ni fusion reaction from gamma-ray multiplicity measurements

Heavy-ion fusion barrier distributions are now routinely obtained directly from experimental data. Measurements of the total y-ray multiplicity for the fusion channels of the 58Ni+60Ni system, which has striking yet well understood barrier structures, confirm the theoretical predictions that very high spins can be populated at energies close to (and even below) the nominal Coulomb barrier. The mapping from multiplicities to spin populations shows that structures in the barrier distribution are still evident in the y-ray results

Influence of fusion barrier distributions on spin populations

Heavy-ion fusion barrier distributions are now routinely obtained directly from experimental data. By measuring the total gamma-ray multiplicity for the Ni-58 + Ni-60 system, which has a striking yet well understood barrier distribution, we show that some evidence of the barrier structures is present in the derived spin populations. In particular, very high spins can be populated at energies rather close to (and even below) the 'nominal' Coulomb barrier.