AI 中文总结
本研究通过检验多种强子模型构建混合中子星态方程，经多类约束及贝叶斯推断后，发现仅eLSM+GMSR(BSK16)构造与观测一致，支持强子-夸克交叉发生于高重子密度，不支持纯夸克核心，且认为GW190817次天体不大可能是中子星。
AI 中文摘要
我们研究通过将扩展线性西格玛模型（extended linear sigma model，缩写为eLSM）描述的夸克物质与几种代表性强子态方程通过平滑的强子-夸克交叉结合构建的混合中子星态方程的天体物理学约束。为探究所得混合态方程的模型依赖性，我们检验了四种不同的强子模型。在施加稳定性、因果性、微扰量子色动力学（perturbative QCD）匹配、潮汐形变以及最大质量约束后，仅eLSM+GMSR(BSK16)构造与当前天体物理学观测完全一致。基于中子星内部组成探测器（NICER）的质量-半径测量结果及GW170817引力波事件，我们利用贝叶斯推断对幸存的参数化方案进一步约束。后验分布支持在相对较高的重子密度下发生宽泛的强子-夸克交叉，而强烈不支持形成延伸的纯夸克核心。相反，当前观测支持包含延伸的混合强子-夸克过渡区域的中子星。我们还研究了推断出的最大质量分布对GW190817次天体的影响，发现在当前模型及采用的观测约束下，将其解释为中子星是不可能的。
英文摘要
We investigate astrophysical constraints on hybrid neutron-star equations of state constructed by combining an extended linear sigma model description of quark matter with several representative hadronic equations of state through a smooth hadron--quark crossover. Four different hadronic models are examined in order to explore the model dependence of the resulting hybrid equations of state. After imposing stability, causality, perturbative QCD matching, tidal deformability, and maximum-mass constraints, only the eLSM+GMSR(BSK16) construction remains fully consistent with current astrophysical observations. The surviving parameterizations are further constrained using Bayesian inference based on NICER mass--radius measurements and the GW170817 gravitational-wave event. The posterior distributions favor a broad hadron--quark crossover occurring at relatively high baryon densities, while the formation of extended pure quark cores is strongly disfavored. Instead, the current observations favor neutron stars containing an extended mixed hadron--quark transition region. We also investigate the implications of the inferred maximum-mass distribution for the secondary object of GW190814 and find that, within the present model and adopted observational constraints, its interpretation as a neutron star is unlikely.
Comments13 pages, 7 figures, 2 tables
