标题： 致密物质状态方程和RMF模型中耦合常数的天体物理限制 显示英文标题

标题： Astrophysical constraints on nuclear EOSs and coupling constants in RMF models

摘要： 利用各种天体物理对中子星结构的约束，我们对RMF模型中耦合常数的密度相关行为以及超核密度下核物质性质进行了贝叶斯分析。 考虑了同标量-标量、同标量-矢量和同位旋-矢量通道中的有效核子相互作用，其中相应的耦合常数（$\alpha_S, \alpha_V, \alpha_{TV}$）通过将整个密度范围划分为三个区域，用六个独立参数来确定。 在这项工作中，我们专注于限制超核密度下的点耦合常数的密度相关性，而亚饱和密度下的耦合常数则从协变密度泛函DD-ME2中推导得出。 对于那些与天体物理观测一致的情况，耦合常数通常随着密度的增加而减小，并在足够大的密度下接近较小的正值，这在定性上与各种RMF模型一致。 还检查了耦合常数及其各种核物质性质后验概率密度函数及其相关性。 在$1\sigma$水准上，密度$1.5n_0$($2.5n_0$) 处的约束耦合常数为$\alpha_S = 3.1^{+0.1}_{-0.05} (1.55^{+0.85}_{-0.2}) \times 10^{-4} \mathrm{MeV}^{-2}$， $\alpha_V = 2.3^{+0.1}_{-0.0} (1.3^{+0.55}_{-0.1}) \times 10^{-4} \mathrm{MeV}^{-2}$和$\alpha_{TV} = 2.05^{+0}_{-0.4} (2.05^{+0}_{-0.5})\times 10^{-5} \mathrm{MeV}^{-2}$。 在更高的密度下，我们发现 $\alpha_{TV}$ 的下限约束不够强，因此有必要进行具有更多自由参数的更广泛的计算。 显示英文摘要

摘要： Utilizing various astrophysical constraints on neutron star structures, we carry out a Bayesian analysis on the density-dependent behaviors of coupling constants in RMF models as well as the nuclear matter properties at supranuclear densities. The effective nucleon interactions in the isoscalar-scalar, isoscalar-vector, and isovector-vector channels are considered, where the corresponding coupling constants ($\alpha_S, \alpha_V, \alpha_{TV}$) are fixed by dividing entire density range into three regions with six independent parameters. In this work we focus on constraining the density-dependent point-coupling constants at supranuclear densities, while the coupling constants at subsaturation densities are derived from the covariant density functional DD-ME2. For those consistent with astrophysical observations, the coupling constants generally decrease with density and approach to small positive values at large enough densities, which qualitatively agrees with various RMF models. The posterior probability density functions and their correlations of the coupling constants and various nuclear matter properties are examined as well. At $1\sigma$ level, the constrained coupling constants at density $1.5n_0$ ($2.5n_0$) are $\alpha_S = 3.1^{+0.1}_{-0.05} (1.55^{+0.85}_{-0.2}) \times 10^{-4} \mathrm{MeV}^{-2}$, $\alpha_V = 2.3^{+0.1}_{-0.0} (1.3^{+0.55}_{-0.1}) \times 10^{-4} \mathrm{MeV}^{-2}$, and $\alpha_{TV} = 2.05^{+0}_{-0.4} (2.05^{+0}_{-0.5})\times 10^{-5} \mathrm{MeV}^{-2}$. At larger densities, we find the lower limit of $\alpha_{TV}$ is not well constrained, so that more extensive calculations with larger number of free parameters are necessary.