Shell evolution and nuclear forces

doi:10.1016/j.physletb.2010.02.051

Physics Letters B

Volume 686, Issues 2–3, 22 March 2010, Pages 109-113

https://doi.org/10.1016/j.physletb.2010.02.051 Get rights and content

Abstract

We present a quantitative study of the role played by different components characterizing the nucleon–nucleon interaction in the evolution of the nuclear shell structure. It is based on the spin–tensor decomposition of an effective two-body shell-model interaction and the subsequent study of effective single-particle energy variations in a series of isotopes or isotones. The technique allows to separate unambiguously contributions of the central, vector and tensor components of the realistic effective interaction. We show that while the global variation of the single-particle energies is due to the central component of the effective interaction, the characteristic behavior of spin–orbit partners, noticed recently, is mainly due to its tensor part. Based on the analysis of a well-fitted realistic interaction in the $s d p f$ shell-model space, we analyze in detail the role played by the different terms in the formation and/or disappearance of $N = 16$ , $N = 20$ and $N = 28$ shell gaps in neutron-rich nuclei.

Section snippets

Note added

The authors have noticed that just recently Otsuka et al. [44] have come to very much the same conclusions as presented in our paper with respect to the need of considering both a central and tensor force to describe the variation in shell structure in a correct and consistent way.

Acknowledgements

N.A.S. thanks M. Hjorth-Jensen for attracting attention to the existence of a spin–tensor decomposition. We are grateful to O. Sorlin for his interest and useful discussions. K.H. thanks the FWO-Vlaanderen for financial support. This research was performed in the framework of the BriX network (P6/23) funded by the ‘IUAP Programme – Belgian State-BSP’. K.S. has been supported by the State of Hesse within the Helmholtz International Center for FAIR (HIC for FAIR) and by the DFG under grant No.

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Shell evolution and nuclear forces

Abstract

Section snippets

Note added

Acknowledgements

Prog. Part. Nucl. Phys.

Prog. Part. Nucl. Phys.

Phys. Lett.

Phys. Rep.

Phys. Lett. B

Phys. Rep.

Nucl. Phys. A

Phys. Lett. B

Prog. Part. Nucl. Phys.

Nucl. Phys. A

Phys. Rev. Lett.

Phys. Rev. Lett.

AIP Conf. Proc.

Phys. Rev. Lett.

Phys. Rev. C

Phys. Rev. C

Phys. Rev. C

Phys. Rev. C

Phys. Rev. C

Phys. Rev. C