Unified equations of state for cold non-accreting neutron stars with Brussels-Montreal functionals. I. Role of symmetry energy

Abstract

The theory of the nuclear energy-density functional is used to provide a\nunified and thermodynamically consistent treatment of all regions of cold\nnon-accreting neutron stars. In order to assess the impact of our lack of\ncomplete knowledge of the density dependence of the symmetry energy on the\nconstitution and the global structure of neutron stars, we employ four\ndifferent functionals. All of them were precision fitted to essentially all the\nnuclear-mass data with the Hartree-Fock-Bogoliubov method and two different\nneutron-matter equations of state based on realistic nuclear forces. For each\nfunctional, we calculate the composition, the pressure-density relation, and\nthe chemical potentials throughout the star. We show that uncertainties in the\nsymmetry energy can significantly affect the theoretical results for the\ncomposition and global structure of neutron stars. To facilitate astrophysical\napplications, we construct analytic fits to our numerical results.\n