An alternative understanding of mass formulas in terms of nuclear structure

M. Hasegawa; K. Kaneko

doi:10.1143/ptp.113.1215

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An alternative understanding of mass formulas in terms of nuclear structure

M. Hasegawa·K. Kaneko

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Abstract

A typical form of mass formula is re-explained in terms of nuclear structure. For $ N \approx Z $ nuclei, we propose to start with the shell model picture and to consider the T=0 $2n-2p$ ($α$-like) correlations as the fundamental concept, instead of the symmetry energy. Subsequently, the symmetry energy is described on the basis of the $α$-like superfluidity caused by the T=0 $2n-2p$ correlations, in parallel with the pairing energy described on the basis of the pairing superfluidity. This re-explanation gives useful insight for understanding the nuclear mass formula. The origin of the Wigner energy is also explained in an interacting boson model for the Cooper pairs in the $α$-like superfluid vacuum. Adding a correction term due to the T=0 $2n-2p$ correlations, which determines the T=0 base level for nuclear masses, can improve the mass formulas in practice.

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M. Hasegawa, K. Kaneko. 2005-05-21. An alternative understanding of mass formulas in terms of nuclear structure. https://doi.org/10.1143/ptp.113.1215

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