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Experimental evidence for 56Ni-core breaking from the low-spin structure of the N=Z nucleus 58Cu

A. F. Lisetskiy·N. Pietralla·M. Honma·A. Schmidt·I. Schneider·A. Gade·P. von Brentano·T. Otsuka·T. Mizusaki·B. A. Brown
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Abstract

Low-spin states in the odd-odd N=Z nucleus 58Cu were investigated with the 58Ni(p,n gamma)58Cu fusion evaporation reaction at the FN-tandem accelerator in Cologne. Seventeen low spin states below 3.6 MeV and 17 new transitions were observed. Ten multipole mixing ratios and 17 gamma-branching ratios were determined for the first time. New detailed spectroscopic information on the 2+,2 state, the Isobaric Analogue State (IAS) of the 2+,1,T=1 state of 58Ni, makes 58Cu the heaviest odd-odd N=Z nucleus with known B(E2;2+,T=1 --> 0+,T=1) value. The 4^+ state at 2.751 MeV, observed here for the first time, is identified as the IAS of the 4+,1,T=1 state in 58Ni. The new data are compared to full pf-shell model calculations with the novel GXPF1 residual interaction and to calculations within a pf5/2 configurational space with a residual surface delta interaction. The role of the 56Ni core excitations for the low-spin structure in 58Cu is discussed.

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A. F. Lisetskiy, N. Pietralla, M. Honma, A. Schmidt, I. Schneider, A. Gade, P. von Brentano, T. Otsuka, T. Mizusaki, B. A. Brown. 2003-06-23. Experimental evidence for 56Ni-core breaking from the low-spin structure of the N=Z nucleus 58Cu. https://doi.org/10.1103/physrevc.68.034316

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