Isobaric analogue states studied in mirrored fragmentation and knockout reactions

摘要

A Gamma-ray spectroscopic study of excited states of isobaric multiplets has been performed in recent years, with a view to gaining a quantitative understanding of energy differences between excited states in terms of a range of Coulomb and other isospin breaking phenomena. Recently, the experimental programme has been augmented by a study of isobaric analogue states of mirror nuclei populated in mirrored fragmentation reactions. In this presentation, recent results on the T = 3/2 analogue states in the T_z = ±3/2 mirror pair ~(53)Ni/~(53)Mn will be summarised. In this work, further strong evidence is found for the need to include an anomalous isospin-breaking two-body matrix element for angular-momentum couplings of J = 2, in addition the expected Coulomb contribution, in order to account for the experimental data.