Dipartimento di Fisica, Sapienza Università di Roma & Sezione INFN Roma1, P.A. Moro 5, 00185, Roma, Italy.
Phys Rev Lett. 2019 Oct 4;123(14):141101. doi: 10.1103/PhysRevLett.123.141101.
Using a Bayesian approach, we combine measurements of neutron star macroscopic observables obtained by astrophysical and gravitational observations to derive joint constraints on the equation of state (EOS) of matter at supranuclear density. In our analysis, we use two sets of data: (i) the masses and tidal deformabilities measured in the binary neutron star event GW170817, detected by LIGO and Virgo, and (ii) the masses and stellar radii measured from observations of nuclear bursts in accreting low-mass x-ray binaries. Using a phenomenological parametrization of the equation of state, we compute the posterior probability distributions of the EOS parameters, using which we infer the posterior distribution for the radius and the mass of the two neutron stars of GW170817. The constraints we set on the radii are tighter than previous bounds.
我们采用贝叶斯方法，将天体物理和引力观测获得的中子星宏观观测结果结合起来，推导出在超核密度下物质状态方程（EOS）的联合约束。在我们的分析中，我们使用了两组数据：（i）通过 LIGO 和 Virgo 探测到的双中子星事件 GW170817 中测量的质量和潮汐变形，以及（ii）从吸积低质量 X 射线双星中核爆观测中测量的质量和恒星半径。我们使用状态方程的一种唯象参数化来计算 EOS 参数的后验概率分布，利用该分布推断出 GW170817 中两个中子星的半径和质量的后验分布。我们对半径的约束比以前的约束更严格。
