New covariant density functionals of nuclear matter for compact star simulations

TL;DR

This paper develops new covariant density functionals for nuclear matter, providing extensive tables of equations of state and parameters for astrophysical simulations of compact stars, including phase transition models.

Contribution

It introduces three families of extended covariant density functionals with varied symmetry energy slopes and skewness, along with comprehensive EOS tables for astrophysical applications.

Findings

Generated 243 equations of state for different parameter variations.

Provided tables of mass, radius, and tidal deformability for compact star modeling.

Included a phase transition to quark matter in one functional family.

Abstract

We generate three families of extended covariant density functionals of nuclear matter that have varying slope of symmetry energy and skewness at nuclear saturation density, but otherwise share the same basic parameters (symmetry energy, compressibility, saturation parameters, etc.) with the standard DDME2, DD2, and MPE functionals. Tables of the parameters of these new density functionals are given, which can be straightforwardly used in DDME2, DD2, and MPE parameterization-based codes. Furthermore, we provide tables of a large number of equations of state (81 for each family) that can be used in astrophysical simulations to assess the impact of variations of not-well-known slope of symmetry energy and skewness of nuclear systems on the astrophysics of compact objects. We also provide tables of computed integral parameters (mass, radius, and tidal deformability) that can be used, e.g., for modeling gravitational waveforms. Finally, for the extended DDME2-based parameterization, we implement a first-order phase transition to quark matter to obtain a family of equations of state that accommodates a phase transition to quark matter. Analogous tables of the equations of state and integral parameters are provided for this case as well.