Experimental and shell-model study of excited states in Fe-55(26)29 and related notes on Cu-55(29)26

The fusion-evaporation reaction S-32+Si-28 at 125-MeV beam energy was used to populate excited states in Fe-55. Combining the Gammasphere spectrometer with ancillary devices including the Microball CsI(Tl) array and a shell of neutron detectors, a comprehensive level scheme could be derived. The experimental results are compared with theoretical results from shell-model calculations. Taking into account isospin-symmetry breaking terms is found to considerably improve the shell-model description for Fe-55. This motivated a predictive case study of near-yrast states in the mirror nucleus Cu-55.