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arXiv · 1903.04875

Suitable resolution for EOS tables in neutron star investigation

Houyuan Chen·Dehua Wen·Na Zhang
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Abstract

Inasmuch as the hydrostatic structure of interior neutron stars uniquely depends on the equation of state (EOS), the inverse constraints on EOS from astrophysical observation have been important methods to reveal the properties of the high-density matter. Up to date, most of EOSs for neutron-star matter are given in tabulations, but these numeric tables could be quite different in resolution. To guarantee both the accuracy and efficiency in computing Tolman-Oppenheimer-Volkoff (TOV) equation, a concise standard for generating EOS tables with suitable resolution is investigated in this work. It is shown that the EOS tables with 50 points logarithmic-uniformly located at supra-nuclear density segment [$ρ_{0}, 10 ρ_{0} $], where $ρ_{0}$ is the nuclear saturation density) would correspond to the interpolation-induced errors at $\sim 0.02\%$ for the gravitational mass $M$ and $\sim 0.2\%$ for the tidal deformability $Λ$.

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Houyuan Chen, Dehua Wen, Na Zhang. 2019-03-12. Suitable resolution for EOS tables in neutron star investigation. https://doi.org/10.1088/1674-1137%2F43%2F5%2F054108

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