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arXiv · 2007.01934

Isospin symmetry breaking in the mirror pair $^{73}$Sr-$^{73}$Br

S. M. Lenzi·A. Poves·A. O. Macchiavelli
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Abstract

The recent experimental observation of isospin symmetry breaking (ISB) in the ground states of the $T=3/2$ mirror pair $^{73}$Sr - $^{73}$Br is theoretically studied using large-scale shell model calculations. The large valence space and the successful PFSDG-U effective interaction used for the nuclear part of the problem capture possible structural changes and provide a robust basis to treat the ISB effects of both electromagnetic and non-electromagnetic origin. The calculated shifts and mirror-energy-differences are consistent with the inversion of the $I^π$= 1/2$^{-}, 5/2^{-}$ states between $^{73}$Sr - $^{73}$Br, and suggest that the role played by the Coulomb interaction is dominant. An isospin breaking contribution of nuclear origin is estimated to be $\approx 25$ keV.

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S. M. Lenzi, A. Poves, A. O. Macchiavelli. 2020-07-08. Isospin symmetry breaking in the mirror pair $^{73}$Sr-$^{73}$Br. https://doi.org/10.1103/physrevc.102.031302

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