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arXiv · 1403.4688

Isospin nonconserving interaction in the T=1 analogue states of the mass-70 region

K. Kaneko·Y. Sun·T. Mizusaki·S. Tazaki
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Abstract

Mirror energy differences (MED) and triplet energy differences (TED) in the T=1 analogue states are important probes of isospin-symmetry breaking. Inspired by the recent spectroscopic data of 66Se, we investigate these quantities for A=66-78 nuclei with large-scale shell-model calculations. For the first time, we find clear evidences suggesting that the isospin nonconserving (INC) nuclear force has a significant effect for the upper fp shell region. Detailed analysis shows that in addition to the INC force, the electromagnetic spin-orbit interaction plays an important role for the large, negative MED in A=66 and 70 and the multipole Coulomb term contributes to the negative TED in all the T=1 triplet nuclei. The INC force and its strength needed to reproduce the experimental data are compared with those from the G-matrix calculation using the modern charge-dependent nucleon-nucleon forces.

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K. Kaneko, Y. Sun, T. Mizusaki, S. Tazaki. 2014-03-19. Isospin nonconserving interaction in the T=1 analogue states of the mass-70 region. https://doi.org/10.1103/physrevc.89.031302

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