Evidence for a beta-decaying 1/2- isomer in 71Ni

I. Stefanescu; D. Pauwels; N. Bree; T. E. Cocolios; J. Diriken; S. Franchoo; M. Huyse; O. Ivanov; Y. Kudryavtsev; N. Patronis; J. Van De Walle; P. Van Duppen; W. B. Walters

doi:10.1103/physrevc.79.044325

arXiv · 0903.1916

Evidence for a beta-decaying 1/2- isomer in 71Ni

I. Stefanescu·D. Pauwels·N. Bree·T. E. Cocolios·J. Diriken·S. Franchoo·M. Huyse·O. Ivanov·Y. Kudryavtsev·N. Patronis·J. Van De Walle·P. Van Duppen·W. B. Walters

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Abstract

We report on the investigation of the population mechanism for the 454-KeV level in 71Cu. This level was identified for the first time in a recent Coulomb excitation measurement with a radioactive beam of 71Cu. The selective nature of the Coulomb-excitation process as well as nuclear-structure considerations constrain the possible spin values for the newly observed state to Ipi=1/2-. A re-examination of the data set obtained in a beta-decay study at the LISOL separator revealed that this state is also populated in the decay of 71Ni, most probably by direct feeding from a newly identified 1/2- beta-decaying isomer having a T1/2=2.34(25) s. In this paper we investigate the proposed scenario by reanalyzing the beta-gamma and gamma-gamma coincidences obtained in the beta-decay study at LISOL.

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I. Stefanescu, D. Pauwels, N. Bree, T. E. Cocolios, J. Diriken, S. Franchoo, M. Huyse, O. Ivanov, Y. Kudryavtsev, N. Patronis, J. Van De Walle, P. Van Duppen, W. B. Walters. 2009-03-11. Evidence for a beta-decaying 1/2- isomer in 71Ni. https://doi.org/10.1103/physrevc.79.044325

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