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Quadrupole strength in isobaric triplets

B. C. Backes1,*, J. Dobaczewski1,2, D. Muir1, W. Nazarewicz3, P.-G. Reinhard4, M. A. Bentley1, and R. Wadsworth1

  • 1School of Physics, Engineering and Technology, University of York, Heslington, York YO10 5DD, United Kingdom
  • 2Institute of Theoretical Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, PL-02-093 Warsaw, Poland
  • 3Facility for Rare Isotope Beams and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
  • 4Institut für Theoretische Physik, Universität Erlangen, Erlangen, Germany

  • *Contact author: betania.backes@york.ac.uk
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Phys. Rev. C 112, 064311 – Published 8 December, 2025

DOI: https://doi.org/10.1103/5wkc-7gmf

Abstract

The dependence of the E2 matrix elements on isospin projection Tz is linked to the conservation of the isospin symmetry. To study this conjecture, we calculated the B(E2:2+→0+) rates for the even-even T=1 mirror nuclei with 42 ≤ A ≤ 98 within nuclear density functional theory, employing the generalized Bohr Hamiltonian, and carrying out angular momentum projection. We demonstrated that collective effects are crucial for describing experimental data near the N=Z line without invoking explicit beyond-Coulomb isospin symmetry-breaking corrections. We also determined the B(E2↓) values for odd-odd Tz=0 nuclei Br70 and Y78 in doubly blocked configurations. We discussed the requirements for accurately describing isobaric analog states and emphasized how current theoretical results should be interpreted within the study of isospin symmetry across isospin triplets.

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Phys. Rev. C 112, 064311– Published 8 December, 2025
  • Received 27 May 2025
  • Accepted 20 October 2025
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