Further explorations of Skyrme-Hartree-Fock-Bogoliubov mass formulas. IX: Constraint of pairing force to $^1S 0$ neutron-matter gap - Nuclear TheoryReportar como inadecuado




Further explorations of Skyrme-Hartree-Fock-Bogoliubov mass formulas. IX: Constraint of pairing force to $^1S 0$ neutron-matter gap - Nuclear Theory - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

Abstract: In this latest of our series of Skyrme-HFB mass models, HFB-16, we introducethe new feature of requiring that the contact pairing force reproduce at eachdensity the $^1S 0$ pairing gap of neutron matter as determined in microscopiccalculations with realistic nucleon-nucleon forces. We retain the earlierconstraints on the Skyrme force of reproducing the energy-density curve ofneutron matter, and of having an isoscalar effective mass of $0.8M$ insymmetric infinite nuclear matter at the saturation density; we also keep therecently adopted device of dropping Coulomb exchange. Furthermore, thecorrection term for the spurious energy of collective motion has a form that isknown to favour fission barriers that are in good agreement with experiment.Despite the extra constraints on the effective force, we have achieved a betterfit to the mass data than any other mean field model, the rms error on the 2149measured masses of nuclei with $N$ and $Z \ge$ 8 having been reduced to 0.632MeV; the improvement is particularly striking for the most neutron-rich nuclei.Moreover, it turns out that even with no flexibility at all remaining for thepairing force, the spectral pairing gaps that we find suggest that leveldensities in good agreement with experiment should be obtained. This new forceis thus particularly well-suited for astrophysical applications, such asstellar nucleosynthesis and neutron-star crusts.



Autor: N. Chamel, S. Goriely, J. M. Pearson

Fuente: https://arxiv.org/







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