发表机构
Indian Institute of Science Education and Research Thiruvananthapuram; Vidyasagar College（印度科学教育研究所特里凡得琅分校; 维迪亚萨加尔学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究提出一种通用分段连续参数化形式来近似致密物质状态方程，并通过两种贝叶斯方法验证其准确性，发现不同状态方程共享共同结构。
AI 中文摘要
致密物质的状态方程（EoS）通常以表格化的压强-能量密度关系形式提供，这使数值实现复杂化，并可能损害热力学一致性。在本工作中，我们提出一种具有通用参数化的普适分段连续函数形式，能够表示一大类致密物质状态方程。我们针对来自CompOSE和LALSimulation数据库的表格化状态方程验证了这一参数化。在初始确定性拟合之后，我们采用了两种不同的贝叶斯方法：一种基于通过向拟合状态方程添加噪声而生成的合成状态方程，另一种基于中子星质量和潮汐形变率的多信使测量。在两种方法中，初始最佳拟合参数均用作参考值。对于所考虑的从极软到极硬的状态方程，所得拟合以足够的精度再现了数据库中定义的表格化状态方程及相关的宏观中子星可观测量。推断参数表现出由分段边界处施加的连续性条件引起的强相关性。在多信使推断下，这些相关性在低密度和中等密度分段中持续存在，但在核心中变弱，反映了当前观测在高密度下的约束能力有限。单一函数形式能够描述源自不同微观框架的状态方程，加上相似参数相关性的重现，表明各种致密物质状态方程可能共享一个共同的底层结构。
英文摘要
Equations of state (EoS) for dense matter are commonly provided in tabulated pressure-energy density relations, complicating numerical implementation and potentially compromising thermodynamic consistency. In this work, we propose a piecewise-continuous analytical form with a common parametrization capable of representing a broad class of dense matter EoSs. We validate this parametrization against tabulated EoSs from the CompOSE and LALSimulation repositories. Following the initial deterministic fitting, we employed two distinct Bayesian approaches: one based on synthetic EoSs generated by adding noise to the fitted EoS and another based on multi-messenger measurements of neutron-star masses and tidal deformabilities. In both approaches, the initial best-fit parameters are used as reference values. For the considered EoSs, spanning from very soft to very stiff, the resulting fits reproduce the tabulated EoSs and the associated macroscopic neutron-star observables in the repositories with sufficient accuracy. The inferred parameters exhibit strong correlations arising from the continuity conditions imposed at the segment boundaries. These correlations persist in the low- and intermediate-density segments under multi-messenger inference but become weak in the core, reflecting the limited constraining power of current observations at high densities. The ability of a single functional form to describe EoSs derived from different microscopic frameworks, together with the recurrence of similar parameter correlations, suggests that diverse dense matter EoSs may share a common underlying structure.
Comments29 pages, 10 captioned figures
