Optimal pair density functional for description of nuclei with large neutron excess
Abstract
Toward a universal description of pairing properties in nuclei far from stability, we extend the energy density functional by enriching the isovector density dependence in the particle-particle channel (pair density functional, pair-DF). We emphasize the necessity of both the linear and quadratic isovector density terms. The parameters are optimized by the Hartree-Fock-Bogoliubov calculation for 156 nuclei of the mass number A=118-196 and the asymmetry parameter (N-Z)/A<0.25. We clarify that the pair-DF should include the isovector density dependence in order to take into account the effect of the isoscalar and isovector effective masses in the particle-hole channel consistently. The different Skyrme forces can give the small difference in the pairing gaps toward the neutron drip line, if the optimal pair-DF consistent with the particle-hole channel is employed.
Cite
@article{arxiv.0812.3197,
title = {Optimal pair density functional for description of nuclei with large neutron excess},
author = {M. Yamagami and Y. R. Shimizu and T. Nakatsukasa},
journal= {arXiv preprint arXiv:0812.3197},
year = {2009}
}
Comments
11 pages, 17 figures. We clarify the connection between the effective masses and the pairing density functional in the revised paper. The justification of the mixed type pairing force is also discussed