Nonuniform matter in neutron star crusts studied by the variational method with thomas-fermi calculations

The equation of state (EOS) for neutron star (NS) crusts is studied in the Thomas-Fermi (TF) approximation using the EOS for uniform nuclear matter obtained by the variational method with the realistic nuclear Hamiltonian. The parameters associated with the nuclear three-body force, which are introduced to describe the saturation properties, are finely adjusted so that the TF calculations for isolated atomic nuclei reproduce the experimental data on masses and charge distributions satisfactorily. The resulting root-mean-square deviation of the masses from the experimental data for mass-measured nuclei is about 3 MeV. With the use of the nuclear EOS thus obtained, the nuclear species in the NS crust at zero temperature are determined. The predicted proton numbers of the nuclei in the NS crust are close to the gross behavior of the results obtained by Negele and Vautherin, while they are larger than those for the EOS obtained by Shen et al. owing to the difference in the symmetry energy. The density profile of NS is calculated with the constructed EOS.