Shell model results for nuclear β−-decay properties of sd-shell nuclei

Praveen C Srivastava,Toshio Suzuki,Anil Kumar

doi:10.1093/ptep/ptaa012

Abstract

Abstract We evaluate the allowed $\beta^-$-decay properties of nuclei with $Z = 8$–$15$ systematically under the framework of the nuclear shell model using the valence space Hamiltonians derived from modern ab initio methods, such as in-medium similarity renormalization group and coupled-cluster theory. For comparison we also show results obtained with fitted interaction derived from chiral effective field theory and phenomenological universal $sd$-shell Hamiltonian version B interaction. We have performed calculations for O $\rightarrow$ F, F $\rightarrow$ Ne, Ne $\rightarrow$ Na, Na $\rightarrow$ Mg, Mg $\rightarrow$ Al, Al $\rightarrow$ Si, Si $\rightarrow$ P, and P $\rightarrow$ S transitions. Theoretical results for $B(GT)$, $\log ft$ values, and half-lives are discussed and compared with the available experimental data.

Highlights

Due to the recent progress in nuclear theory with the development of modern effective nucleon– nucleon interactions for sd-shell nuclei, it is possible to predict nuclear observables with appropriate accuracy
The value for universal sd-shell Hamiltonian version B (USDB), q = 0.77 ± 0.02, is consistent with the value q = 0.764 obtained for the USDB by the shell model in the sd shell as reported in Ref. [48]
We see that the RMS deviations for the ab initio and chiral effective field theory (CEFT) interactions are slightly higher than for the USDB interaction

Summary

Introduction

Due to the recent progress in nuclear theory with the development of modern effective nucleon– nucleon interactions for sd-shell nuclei, it is possible to predict nuclear observables with appropriate accuracy. Shell model calculations for β−-decay properties of neutron-rich Z = 9–13 nuclei with N ≥ 18 were reported by Li and Ren in Ref. Our aim is to study the β−-decay properties of Z = 8–15 nuclei corresponding to earlier and new experimental data within the framework of the nuclear shell model using modern ab initio interactions. Our purpose is to study how well the recent ab initio and newly developed shell model interactions based on chiral interactions can describe the β-decay properties in the sd-shell, and to find how much quenching is necessary for these interactions by comparing with much more experimental data than in Ref.

Ab initio Hamiltonians

Results and discussions

Summary and conclusions