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arXiv · 1012.3794

Simplified modeling of cluster-shell competition in $^{20}$Ne and $^{24}$Mg

N. Itagaki·J. Cseh·M. Płoszajczak
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Abstract

We investigate properties of the Generator Coordinate Method (GCM) on a collective basis of Antisymmetrized Quasi-Cluster (AQC) states to describe the cluster-shell competition in $^{20}$Ne and $^{24}$Mg due to the spin-orbit interaction. By introducing a single additional parameter in the antisymmetrized-cluster basis function, a continuous transformation of the $\alpha$ cluster(s) into independent nucleons can be described. We apply this GCM trial wave function to study in details the transition from cluster states $[ ^{16}$O+$\alpha ]$ and $[ ^{16}$O+$\alpha + \alpha]$ to shell model (SM) states $[ ^{16}$O+${\rm 4N} ]$ and $[ ^{16}$O+${\rm 8N} ]$, respectively. An optimal value of the strength of the spin-orbit interaction is deduced by reproducing level spacing in $^{20}$Ne. A possible connection to the group theoretical understanding of the cluster-shell configuration transition is also discussed.

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N. Itagaki, J. Cseh, M. Płoszajczak. 2010-12-17. Simplified modeling of cluster-shell competition in $^{20}$Ne and $^{24}$Mg. https://doi.org/10.1103/physrevc.83.014302

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