Shape Isomerism at N = 40: Discovery of a Proton Intruder in 67Co

D. Pauwels; O. Ivanov; J. Buscher; T. E. Cocolios; J. Gentens; M. Huyse; A. Korgul; Yu. Kudryavtsev; R. Raabe; M. Sawicka; I. Stefanescu; J. Van de Walle; P. Van den Bergh; P. Van Duppen; W. B. Walters

doi:10.1103/physrevc.78.041307

arXiv · 0807.2595

Shape Isomerism at N = 40: Discovery of a Proton Intruder in 67Co

D. Pauwels·O. Ivanov·J. Buscher·T. E. Cocolios·J. Gentens·M. Huyse·A. Korgul·Yu. Kudryavtsev·R. Raabe·M. Sawicka·I. Stefanescu·J. Van de Walle·P. Van den Bergh·P. Van Duppen·W. B. Walters

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Abstract

The nuclear structure of 67Co has been investigated through 67Fe beta-decay. The 67Fe isotopes were produced at the LISOL facility in proton-induced fission of 238U and selected using resonant laser ionization combined with mass separation. The application of a new correlation technique unambiguously revealed a 496(33) ms isomeric state in 67Co at an unexpected low energy of 492 keV. A 67Co level scheme has been deduced. Proposed spin and parities suggest a spherical (7/2-) 67Co ground state and a deformed first excited (1/2-) state at 492 keV, interpreted as a proton 1p-2h prolate intruder state.

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D. Pauwels, O. Ivanov, J. Buscher, T. E. Cocolios, J. Gentens, M. Huyse, A. Korgul, Yu. Kudryavtsev, R. Raabe, M. Sawicka, I. Stefanescu, J. Van de Walle, P. Van den Bergh, P. Van Duppen, W. B. Walters. 2008-07-16. Shape Isomerism at N = 40: Discovery of a Proton Intruder in 67Co. https://doi.org/10.1103/physrevc.78.041307

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