Abstract
Background: The presence of neutron transfer channels with positive Q values can enhance sub-barrier fusion cross sections. Recent measurements of the fusion excitation functions for Ni58+Sn132,124 found that the fusion enhancement due to the influence of neutron transfer is smaller than that in Ca40+Sn132,124 although the Q values for multineutron transfer are comparable. Purpose: To investigate the differences observed between the fusion of Sn + Ni and Sn + Ca. Methods: Fusion excitation functions for Ti46,50+Sn124 have been measured at energies near the Coulomb barrier. Results: A comparison of the barrier distributions for Ti46+Sn124 and Ca40+Sn124 shows that the Ca40+Sn124 system has a barrier strength resulting from the coupling to the very collective octupole state in Ca40 at an energy significantly lower than the uncoupled barrier. Conclusions: The large sub-barrier fusion enhancement in Ca40 induced reactions is attributed to both couplings to neutron transfer and inelastic excitation, with the octupole vibration of Ca40 playing a major role.
| Original language | English |
|---|---|
| Article number | 024616 |
| Journal | Physical Review C |
| Volume | 94 |
| Issue number | 2 |
| DOIs | |
| State | Published - Aug 24 2016 |
Funding
This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics and this research used resources of the Holifield Radioactive Ion Beam Facility of Oak Ridge National Laboratory, which was a DOE Office of Science User Facility. Research at ANU was supported by the Australian Research Council Grants DP130101569, FT120100760, DP140101337, FL110100098, DE140100784 and by National Collaborative Research Infrastructure Strategy (NCRIS) for the operation of the Heavy Ion Accelerator Facility.