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arXiv · 0811.0279

Shell-structure fingerprints of tensor interaction

M. Zalewski·W. Satula·J. Dobaczewski·P. Olbratowski·M. Rafalski·T. R. Werner·R. A. Wyss
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Abstract

We address consequences of strong tensor and weak spin-orbit terms in the local energy density functional, resulting from fits to the $f_{5/2} - f_{7/2}$ splittings in $^{40}$Ca, $^{48}$Ca, and $^{56}$Ni. In this study, we focus on nuclear binding energies. In particular, we show that the tensor contribution to the binding energies exhibits interesting topological features closely resembling that of the shell-correction. We demonstrate that in the extreme single-particle scenario at spherical shape, the tensor contribution shows tensorial magic numbers equal to $N(Z)$=14, 32, 56, and 90, and that this structure is smeared out due to configuration mixing caused by pairing correlations and migration of proton/neutron sub-shells with neutron/proton shell filling. Based on a specific Skyrme-type functional SLy4$_T$, we show that the proton tensorial magic numbers shift with increasing neutron excess to $Z$=14, 28, and 50.

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M. Zalewski, W. Satula, J. Dobaczewski, P. Olbratowski, M. Rafalski, T. R. Werner, R. A. Wyss. 2008-11-03. Shell-structure fingerprints of tensor interaction. https://doi.org/10.1140/epja/i2008-10768-1

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