par Goriely, Stéphane 
;Samyn, Mathieu ;Heenen, Paul-Henri ;Pearson, Michael J.;Tondeur, François
Référence Physical Review C (Nuclear Physics)
Publication Publié, 2002
;Samyn, Mathieu ;Heenen, Paul-Henri ;Pearson, Michael J.;Tondeur, François Référence Physical Review C (Nuclear Physics)
Publication Publié, 2002
Article révisé par les pairs
| Résumé : | The two previously published Hartree-Fock (HF) mass formulas, HFBCS-1 and HFB-1 (HF-Bogoliubov), are shown to be in poor agreement with new Audi-Wapstra mass data. The problem lies first with the prescription adopted for the cutoff of the single-particle spectrum used with the [Formula Presented]-function pairing force, and second with the Wigner term. We find an optimal mass fit if the spectrum is cut off both above [Formula Presented] and below [Formula Presented] being the Fermi energy of the nucleus in question. In addition to the Wigner term of the form [Formula Presented] already included in the two earlier HF mass formulas, we find that a second Wigner term linear in [Formula Presented] leads to a significant improvement in lighter nuclei. These two features are incorporated into our new Hartree-Fock-Bogoliubov model, which leads to much improved extrapolations. The 18 parameters of the model are fitted to the 2135 measured masses for [Formula Presented] with an rms error of 0.674 MeV. With this parameter set a complete mass table, labeled HFB-2, has been constructed, going from one drip line to the other, up to [Formula Presented] The new pairing-cutoff prescription favored by the new mass data leads to weaker neutron-shell gaps in neutron-rich nuclei. © 2002 The American Physical Society. |
