New evidence for a subshell gap at N=32

doi:10.1016/S0370-2693(01)00565-2

Physics Letters B

Volume 510, Issues 1–4, 21 June 2001, Pages 17-23

https://doi.org/10.1016/S0370-2693(01)00565-2 Get rights and content

Abstract

An 879.9(2) keV γ-ray transition has been identified following the β decay of ⁵⁸V and assigned as the 2⁺₁→0⁺₁ transition in ⁵⁸Cr₃₄. A peak in the energies of the first excited 2⁺ states for the even–even chromium isotopes is now evident at ⁵⁶Cr₃₂, providing empirical evidence for a significant subshell gap at N=32. The appearance of this neutron subshell closure for neutron-rich nuclides may be attributed to the diminished π1f_7/2–ν1f_5/2 monopole proton–neutron interaction as protons are removed from the 1f_7/2 single-particle orbital.

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Acknowledgements

This work was supported in part by the National Science Foundation under Grant Nos. PHY-9528844, PHY-0070911 and PHY-9970991. We thank the operations staff of the NSCL for the successful completion of these measurements. We acknowledge the ECR group at the NSCL for development of the ⁷⁰Zn primary beam and M. Steiner for identifying and tuning the secondary beam.

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New evidence for a subshell gap at N=32

Abstract

Section snippets

Acknowledgements

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Nucl. Data Sheets

Nucl. Phys. A

Elementary Theory of Nuclear Shell Structure

Phys. Rev. Lett.

Table of Isotopes, 8th edn., Vol. 1

Phys. Rev. Lett.