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Core breaking at low spin in Zn68 from nuclear resonance fluorescence

S. R. Johnson1,2,*, R. V. F. Janssens1,2, B. A. Brown3,4, A. D. Ayangeakaa1,2, S. S. Bhattacharjee5, E. Churchman1,2, S. W. Finch2,6, U. Friman-Gayer2,6, S. Frye1,2 et al.

M. Fulghieri1,2,†, D. Gribble1,2, X. H.-K. James1,2, R. Longland2,7, and C. Wegner1,2

  • *Present address: Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202, USA and Triangle Universities Nuclear Laboratory, Duke University, Durham, North Carolina 27708, USA.
  • †Present address: Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
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Phys. Rev. C 114, 034318 – Published 15 September, 2026

DOI: https://doi.org/10.1103/hfk6-hmvf

Abstract

Low-spin excited states in Zn68 have been studied at the High Intensity Gamma-Ray Source (HIγS) from the ground state up to the particle emission threshold using the nuclear resonance fluorescence technique and the newly developed clover array. Low-spin levels were excited by linearly polarized, 2.90–9.79 MeV photon beams. Spin-parity quantum numbers as well as associated M1 and E1 decay strengths were determined for a large fraction of the 158 states observed. In addition, long-duration coincidence measurements at 9.46 and 9.79 MeV enabled the investigation of the level scheme near the ground state. The results have been interpreted with shell-model calculations using two different model spaces and several effective interactions often used to describe nuclei in this mass region. While the structure near the ground state can be understood in terms of excitations involving solely valence nucleons, core breaking is required to account for the evolution of the total M1 strength at excitation energies above approximately 5 MeV.

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Outline

Information

Phys. Rev. C 114, 034318– Published 15 September, 2026
  • Received 6 April 2026
  • Revised 30 May 2026
  • Accepted 20 August 2026
Article part of CHORUS
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