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DOE OSTI · 1851239

Shell-model study of calcium isotopes toward their drip line

Coraggio, L.·De Gregorio, G.·Gargano, A.·Itaco, N.·Fukui, T.·Ma, Y. Z.·Xu, F. R.
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Abstract

Here, we report in this paper a study in terms of the nuclear shell model about the location of the calcium isotopes drip line. The starting point is considering the realistic two-body potential derived by Entem and Machleidt within chiral perturbation theory at next-to-next-to-next-to-leading order (N 3 LO), as well as a chiral three-body force at next-to-next-to-leading order (N 2 LO) whose structure and low-energy constants are consistent with the two-body potential. Then we construct the effective single-particle energies and residual interaction needed to diagonalize the shell-model Hamiltonian. The calculated two-neutron separation energies agree nicely with experiment until 56 Ca, which is the heaviest isotope whose mass has been measured, and do not show any sign of two-neutron emission until 70 Ca . We discuss the role of the choice of the model space in determining the neutron drip line, and also the dependence of the results on the parameters of the shell-model Hamiltonian.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSbinding energyenergy levelsfirst-principles calculationslevel densitiesmassesnuclear decaysnuclear forcesnuclear structureperturbation theoryquantum theoryshell model

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Coraggio, L., De Gregorio, G., Gargano, A., Itaco, N., Fukui, T., Ma, Y. Z., Xu, F. R.. 2020-11-23. Shell-model study of calcium isotopes toward their drip line. https://doi.org/10.1103/physrevc.102.054326

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