发表机构
University of Warsaw（华沙大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究建立了适用于均匀旋转、差速旋转及强磁化中子星的转动惯量与致密性广义准普适关系，推导了依赖关系的解析表达式，可用于磁星光度及GW170817遗迹转动动能的相关估计。
AI 中文摘要
中子星宏观性质间的普适关系为探测其内部结构提供了有力框架，同时可最小化与物态方程（EoS）相关的不确定性。尽管这类关系已被广泛研究均匀旋转中子星的情况，但其向差速旋转和强磁化构型的扩展仍在很大程度上未被探索。我们针对大范围的物态方程（EoS）、旋转轮廓和磁场强度系统地研究平衡构型，建立了转动惯量与致密性之间的广义准普适关系，该关系在均匀旋转、差速旋转和强磁化构型下对底层物态方程（EoS）表现出显著的不敏感性。对于角动量固定的序列，归一化转动惯量呈现出对致密性的准普适依赖，偏差主要源于磁场强度和差速旋转程度。我们推导了这些依赖关系的解析表达式，得到可适用于大范围恒星构型的统一唯象模型。作为天体物理应用，我们量化了磁星光度估计的系统偏差以及GW170817并合后遗迹的转动动能。这些结果将准普适关系扩展至均匀旋转和弱磁化的标准假设之外，为解释高度磁化和差速旋转中子星的观测提供了可靠框架，并能对其天体物理性质进行更可靠的约束。
英文摘要
Universal relations among macroscopic properties of neutron stars provide a powerful framework to probe their internal structures while minimizing uncertainties associated with the equation of state (EoS). Although such relations have been extensively studied for uniformly rotating stars, their extension to differentially rotating and strongly magnetized configurations is relatively less explored. We systematically investigate equilibrium configurations for a wide range of EoSs, rotation profiles, and magnetic field strengths with XNS numerical simulation code. For sequences with fixed angular momentum, we analyze the dependence of normalized moment of inertia on compactness. We establish a generalized quasi-universal relation between the moment of inertia and compactness that remains remarkably insensitive to the underlying EoS across uniformly rotating, differentially rotating, and strongly magnetized toroidal configurations. For sequences with fixed angular momentum, the normalized moment of inertia exhibits a quasi-universal dependence on compactness, with deviations primarily due to magnetic field strength and degree of differential rotation. We derive analytic expressions for these dependencies, enabling a unified phenomenological model applicable over a wide range of stellar configurations. As astrophysical applications, we quantify the systematic bias in magnetar luminosity estimates and the rotational kinetic energy of post-merger remnant of GW170817. These results extend quasi-universal relations beyond the standard assumptions of uniform rotation and weak magnetization, providing a robust framework for interpreting observations of highly magnetized and differentially rotating neutron stars, and enabling more reliable constraints on their astrophysical properties.
Comments10 pages with 6 figures and 3 tables; accepted for publication in Astronomy & Astrophysics
