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The Origin of the Wigner Energy

W. Satuła·D. J. Dean·J. Gary·S. Mizutori·W. Nazarewicz
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Abstract

Surfaces of experimental masses of even-even and odd-odd nuclei exhibit a sharp slope discontinuity at N=Z. This cusp (Wigner energy), reflecting an additional binding in nuclei with neutrons and protons occupying the same shell model orbitals, is usually attributed to neutron-proton pairing correlations. A method is developed to extract the Wigner term from experimental data. Both empirical arguments and shell-model calculations suggest that the Wigner term can be traced back to the isospin T=0 part of nuclear interaction. Our calculations reveal the rather complex mechanism responsible for the nuclear binding around the N=Z line. In particular, we find that the Wigner term cannot be solely explained in terms of correlations between the neutron-proton J=1, T=0 (deuteron-like) pairs.

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W. Satuła, D. J. Dean, J. Gary, S. Mizutori, W. Nazarewicz. 1997-02-27. The Origin of the Wigner Energy. https://doi.org/10.1016/s0370-2693(97)00711-9

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