2000/03/27 by N. Itagaki, S. Okabe, Satoshi Okabe +1 · 2 citations
Physics and Astronomy · #Advanced Chemical Physics Studies #Atomic and Molecular Physics #Nuclear physics research studies #nucl-th
paper · pdf · doi:10.1103/physrevc.62.034301
published as Phys.Rev. C62 (2000) 034301 · 14 pages, 4 figures
arxiv created 2000/03/27 · openalex publication_date 2000/07/26 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The structure of the second 0+ state of 10Be is investigated using a microscopic \ensuremathα+\ensuremathα+n+n model based on the molecular-orbit (MO) model. The second 0+ state, which has dominantly the (1/2+)2 configuration, is shown to have a particularly enlarged \ensuremathα-\ensuremathα structure. The kinetic energy of the two valence neutrons occupying along the \ensuremathα-\ensuremathα axis is reduced remarkably due to the strong \ensuremathα clustering and, simultaneously, the spin-orbit interaction unexpectedly plays an important role in making the energy of this state much lower. The mixing of states with different spin structure is shown to be important in negative-parity states. The experimentally observed small-level spacing between 1^\ensuremath- and 2^\ensuremath- (\ensuremath∼300 keV) is found to be evidence of this spin-mixing effect. 12Be is also investigated using the \ensuremathα+\ensuremathα+4n model, in which four valence neutrons are considered to occupy the (3/2^\ensuremath-)2(1/2+)2 configuration. The energy surface of 12Be is shown to exhibit similar characteristics, that the remarkable \ensuremathα clustering and the contribution of the spin-orbit interaction make the binding of the state with the (3/2^\ensuremath-)2(1/2+)2 configuration properly stronger in comparison with the closed p-shell (3/2^\ensuremath-)2(1/2^\ensuremath-)2 configuration.