Woods-Saxon-Gaussian potential and alpha-cluster structures ofalpha + closed shell nuclei
- Received Date: 2018-07-11
- Available Online: 2018-12-05
Abstract: The Woods-Saxon-Gaussian (WSG) potential is proposed as a new phenomenological potential to systematically describe the level scheme, electromagnetic transitions, and alpha-decay half-lives of the alpha-cluster structures in various alpha + closed shell nuclei. It modifies the original Woods-Saxon (WS) potential with a shifted Gaussian factor centered at the nuclear surface. The free parameters in the WSG potential are determined by reproducing the correct level scheme of 212Po=208Pb+α. It is found that the resulting WSG potential matches the M3Y double-folding potential at the surface region and makes corrections to the inner part of the cluster-core potential. It was also determined that the WSG potential, with nearly identical parameters to that of 212Po (except for a rescaled radius), could also be used to describe alpha-cluster structures in 20Ne=16O+α and 44Ti=40Ca+α. In all three cases, the calculated values of the level schemes, electromagnetic transitions, and alpha-decay half-lives agree with the experimental data, which indicates that the WSG potential could indeed capture many important features of the alpha-cluster structures in alpha + closed shell nuclei. This study is a useful complement to the existing cluster-core potentials in literature. The Gaussian form factor centered at the nuclear surface might also help to improve our understanding of the alpha-cluster formation, which occurs in the same general region.