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arXiv · 1404.0603

Effects of the tensor force on the ground and first $2^{+}$ states of the magic $^{54}$Ca nucleus

E. Yüksel·N. Van Giai·E. Khan·K. Bozkurt
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Abstract

The magic nature of the $^{54}$Ca nucleus is investigated in the light of the recent experimental results. We employ both HFB and HF+BCS methods using Skyrme-type SLy5, SLy5+T and T44 interactions. The evolution of the single-particle spectra is studied for the N=34 isotones: $^{60}$Fe, $^{58}$Cr, $^{56}$Ti and $^{54}$Ca. An increase is obtained in the neutron spin-orbit splittings of $p$ and $f$ states due to the effect of the tensor force which also makes $^{54}$Ca a magic nucleus candidate. QRPA calculations on top of HF+BCS are performed to investigate the first $J^π$=$2^{+}$ states of the calcium isotopic chain. A good agreement for excitation energies is obtained when we include the tensor force in the mean-field part of the calculations. The first $2^{+}$ states indicate a subshell closure for both $^{52}$Ca and $^{54}$Ca nuclei. We confirm that the tensor part of the interaction is quite essential in explaining the neutron subshell closure in $^{52}$Ca and $^{54}$Ca nuclei.

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E. Yüksel, N. Van Giai, E. Khan, K. Bozkurt. 2014-06-30. Effects of the tensor force on the ground and first $2^{+}$ states of the magic $^{54}$Ca nucleus. https://doi.org/10.1103/physrevc.89.064322

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