Isospin symmetry breaking at high spins in the mirror pair 67Se and 67As

Abstract

Recent experimental data have revealed large mirror energy differences (MED) between high-spin states in the mirror nuclei 67Se and 67As, the heaviest pair where MED have been determined so far. The MED are generally attributed to the isospin symmetry breaking caused by the Coulomb force and by the isospin nonconserving part of the nucleon-nucleon residual interaction. The different contributions of the various terms have been extensively studied in the fp shell. By employing large-scale shell model calculations, we show that the inclusion of the g9/2 orbit causes interference between the electromagnetic spin-orbit and the Coulomb monopole radial terms at high spin. The large MED are attributed to the aligned proton pair excitations from the p3/2 and f5/2 orbits to the g9/2 orbit. The relation of the MED to deformation is discussed.

arXiv comment5 pages, 4 figures, accepted in Phys. Rev. C

References in corpus (6)

• A Full $PF$ Shell Model Study of a~=~48 Nuclei
• Isobaric multiplet yrast energies and isospin non-conserving forces
• Mirror displacement energies and neutron skins
• Coulomb shifts and shape changes in the mass 70 region
• Rotation alignment in neutron-rich Cr isotopes: A probe of deformed single-particle levels across N=40
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Cited by in corpus (7)

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• Isospin nonconserving interaction in the T=1 analogue states of the mass-70 region
• Mirror Energy Differences at Large Isospin Studied through Direct Two-Nucleon Knockout
• Toward ab initio charge symmetry breaking in nuclear energy density functionals
• Effects of Coulomb and isospin symmetry breaking interactions on neutron-skin thickness