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arXiv · 2203.08521

Nearly model-independent constraints on dense matter equation of state in a Bayesian approach

N. K. Patra·Sk Md Adil Imam·B. K. Agrawal·Arunava Mukherjee·Tuhin Malik
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Abstract

We apply Bayesian approach to construct a large number of minimally constrained equations of state (EOSs) and study their correlations with a few selected properties of a neutron star (NS). Our set of minimal constraints includes a few basic properties of saturated nuclear matter and low-density pure neutron matter EOS which is obtained from a precise next-to-next-to-next-to-leading-order (N$^{3}$LO) calculation in chiral effective field theory. The tidal deformability and radius of NS with mass $1-2 M_\odot$ are found to be strongly correlated with the pressure of $β$-equilibrated matter at densities higher than the saturation density ($ρ_0 = 0.16$ fm$^{-3}$) in a nearly model-independent manner. These correlations are employed to parametrize the pressure for $β$-equilibrated matter, around 2$ρ_0$, as a function of neutron star mass and the corresponding tidal deformability. The maximum mass of neutron star is also found to be strongly correlated with the pressure of $β$-equilibrated matter at densities $\sim 4.5ρ_0$.

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N. K. Patra, Sk Md Adil Imam, B. K. Agrawal, Arunava Mukherjee, Tuhin Malik. 2022-08-09. Nearly model-independent constraints on dense matter equation of state in a Bayesian approach. https://doi.org/10.1103/physrevd.106.043024

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