A new strategy of fitting the coupling constants of the nuclear energy density functional is proposed, which shifts attention from ground-state bulk to single-particle properties. The latter are analyzed in terms of the bare single-particle energies and mass, shape, and spin core-polarization effects. Fit of the isoscalar spin-orbit and both isoscalar and isovector tensor coupling constants directly to the f 5/2 − f 7/2 spin-orbit splittings in 40 Ca, 56 Ni, and 48 Ca is proposed as a practical realization of this new programme. It is shown that this fit requires drastic changes in the isoscalar spin-orbit strength and the tensor coupling constants as compared to the commonly accepted values but it considerably and systematically improves basic single-particle properties including spin-orbit splittings and magic-gap energies. Impact of these changes on nuclear binding energies is also discussed.

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We perform a systematic shell-model and mean-field study of fully-aligned, high-spin f n 7/2 seniority isomers and d −13/2 f n+1 7/2 intruder states in the A∼44 nuclei from the lower-f p shell. The shell-model calculations are performed in the full sdf p configuration space allowing 1p-1h cross-shell excitations. The self-consistent mean-field calculations are based on the Hartree-Fock approach with the Skyrme energy density functional that reproduces empirical Landau parameters. While there is a nice agreement between experimental and theoretical relative energies of fully-aligned states in N >Z nuclei, this is no longer the case for the N =Z systems. The remaining deviation from the data is attributed to the isoscalar proton-neutron correlations. It is also demonstrated that the Coulomb corrections at high spins noticeably depend on the choice of the energy density functional.

A direct fit of the isoscalar spin-orbit (SO) and both isoscalar and isovector tensor coupling constants to the f 5/2 − f 7/2 SO splittings in 40 Ca, 56 Ni, and 48 Ca nuclei requires a drastic reduction of the isoscalar SO strength and strong attractive tensor coupling constants. The aim of this work is to address further consequences of these strong attractive tensor and weak SO fields on binding energies, nuclear deformability, and high-spin states. In particular, we show that contribution to the nuclear binding energy due to the tensor field shows generic magic structure with the tensorial magic numbers at N (Z)=14, 32, 56, or 90 corresponding to the maximum spin-asymmetries in 1d 5/2 , 1f 7/2 ⊕ 2p 3/2 , 1g 9/2 ⊕ 2d 5/2 and 1h 11/2 ⊕ 2f 7/2 single-particle configurations and that these numbers are smeared out by pairing correlations and deformation effects. We also examine the consequences of strong attractive tensor fields and weak SO interaction on nuclear stability at the drip lines, in particular close to the tensorial doubly magic nuclei and discuss the possibility of an entirely new tensor-force driven deformation effect.

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 SLy4T , we show that the proton tensorial magic numbers shift with increasing neutron excess to Z=14, 28, and 50.PACS. 21.60.Jz Nuclear Density Functional Theory and extensions (includes Hartree-Fock and randomphase approximations) 21.60.-n Nuclear structure models and methods