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arXiv · 1707.06511

Effect of Finite Binding on the Apparent Spin-Orbit Splitting in Nuclei

B. P. Kay·C. R. Hoffman·A. O. Macchiavelli
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Abstract

The apparent splitting between orbitals that are spin-orbit partners can be substantially influenced by the effects of finite binding. In particular, such effects can account for the observed decrease in separation of the neutron $1p_{3/2}$ and $1p_{1/2}$ orbitals between the $^{41}$Ca and $^{35}$Si isotopes. This behavior has been the subject of recent experimental and theoretical works and cited as evidence for a proton "bubble" in $^{34}$Si causing an explicit weakening of the spin-orbit interaction. The results reported here suggest that the change in the separation between the $1p_{3/2}$ and $1p_{1/2}$ partners occurs dominantly because of the behavior of the energies of these $1p$ neutron states near zero binding.

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B. P. Kay, C. R. Hoffman, A. O. Macchiavelli. 2017-07-20. Effect of Finite Binding on the Apparent Spin-Orbit Splitting in Nuclei. https://doi.org/10.1103/physrevlett.119.182502

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