Spectroscopy of proton-rich 66Se up to Jπ=6+: Isospin-breaking effect in the A=66 isobaric triplet

Abstract

Candidates for three excited states in the 66Se have been identified using the recoil-β tagging method together with a veto detector for charged-particle evaporation channels. These results allow a comparison of mirror and triplet energy differences between analog states across the A=66 triplet as a function of angular momentum. The extracted triplet energy differences follow the negative trend observed in the f7/2 shell. Shell-model calculations indicate that the strength of the Coulomb isotensor part alone is not sufficient to account for this trend in the case of the A=66 triplet. © 2013 American Physical Society.