Cluster-shell competition in light nuclei

Abstract

We demonstrate whether the cluster structure dissolves or remains when the shell-model-like model space is introduced in addition to the cluster model space in light nuclei. Although the binding energies of 8Be, 10Be, and 10B become larger by about 1-2 MeV by adding shell-model-like basis states to the α+α+N+N+⋯ basis states, the α-α structure is a dominant configuration of the ground states. However, α-breaking wave functions strongly mix in 12C, and the decrease of the energy from the 3α configuration by about 6 MeV is a clue to resolving a long-standing problem of the binding energies of 12C and 12O. The improved version of antisymmetrized molecular dynamics (AMD), AMD superposition of selected snapshots (AMD triple-S), is used to show the cluster-shell competition of these nuclei.