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How magic is the magic 68Ni nucleus?

K. Langanke·J. Terasaki·F. Nowacki·D. J. Dean·W. Nazarewicz
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Abstract

We calculate the B(E2) strength in 68Ni and other nickel isotopes using several theoretical approaches. We find that in 68Ni the gamma transition to the first 2+ state exhausts only a fraction of the total B(E2) strength, which is mainly collected in excited states around 5 MeV. This effect is sensitive to the energy splitting between the fp shell and the g_{9/2}orbital. We argue that the small experimental B(E2) value is not strong evidence for the double-magic character of 68Ni.

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K. Langanke, J. Terasaki, F. Nowacki, D. J. Dean, W. Nazarewicz. 2002-10-31. How magic is the magic 68Ni nucleus?. https://doi.org/10.1103/physrevc.67.044314

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