Impact of shell structure on the fusion of neutron-rich mid-mass nuclei

The influence of shell effects on fusion of mid-mass nuclei is explored using isotopic chains of K and Ar ions on an oxygen target. Comparison of the reduced excitation functions reveals that the fusion cross section for the open neutron-shell projectile nuclei K-41 and K-45 is systematically larger than for the closed neutron-shell projectiles K-39 and K-47. The Sao Paulo fusion model using matter densities from systematics fails to describe the measured excitation functions. Use of more realistic densities from a Dirac-Hartree-Bogoliubov (DHB) approach performs significantly better though it still overpredicts the closed-shell nuclei.

Automated summary

The study found that shell effects have a significant impact on fusion cross sections of mid-mass nuclei, with different neutron shell structures leading to different outcomes. The use of a more realistic density model can more accurately describe experimental measurements, although it still tends to overpredict closed-shell nuclei.