论文标题
大质量约束对中子恒星特性的影响
Impact of large-mass constraints on the properties of neutron stars
论文作者
论文摘要
非旋转中子恒星的最大质量，$ m _ {\ rm tov} $，在破译中子恒星的结构和组成以及揭示核物质状态（EOS）方程方面起着非常重要的作用。 Although with a large-error bar, the recent mass estimate for the black-widow binary pulsar PSR J0952-0607, i.e. $M=2.35\pm0.17~M_\odot$, provides the strongest lower bound on $M_{\rm TOV}$ and suggests that neutron stars with very large masses can in principle be observed.通过对EOS的不可知论建模，我们研究了大群众对中子星特性的影响。特别是，我们表明，假设$ m _ {\ rm tov} \ gtrsim 2.35 \，m_ \ odot $紧密地约束压力的行为，并将恒星半径的下限移动到恒星半径的下限中，这些值比尼氏菌（Nicer Mealutements）构成了效果，这些值大大约束了，则在底层测量中构成了效果。我们还根据chirp质量为二进制潮汐变形性的下限提供了更新的分析表达式，并显示了$ m _ {\ rm tov} $上更大的界限导致此数量的更严格的约束。此外，我们指出了中子恒星内部压力曲线的新型准宇宙关系，该关系仅依赖于EOS和最大质量约束。最后，我们研究了声速和保形异常是如何分布在中子恒星内的，并显示这些量如何取决于施加的最大质量约束。
The maximum mass of a nonrotating neutron star, $M_{\rm TOV}$, plays a very important role in deciphering the structure and composition of neutron stars and in revealing the equation of state (EOS) of nuclear matter. Although with a large-error bar, the recent mass estimate for the black-widow binary pulsar PSR J0952-0607, i.e. $M=2.35\pm0.17~M_\odot$, provides the strongest lower bound on $M_{\rm TOV}$ and suggests that neutron stars with very large masses can in principle be observed. Adopting an agnostic modelling of the EOS, we study the impact that large masses have on the neutron-star properties. In particular, we show that assuming $M_{\rm TOV}\gtrsim 2.35\,M_\odot$ constrains tightly the behaviour of the pressure as a function of the energy density and moves the lower bounds for the stellar radii to values that are significantly larger than those constrained by the NICER measurements, rendering the latter ineffective in constraining the EOS. We also provide updated analytic expressions for the lower bound on the binary tidal deformability in terms of the chirp mass and show how larger bounds on $M_{\rm TOV}$ lead to tighter constraints for this quantity. In addition, we point out a novel quasi-universal relation for the pressure profile inside neutron stars that is only weakly dependent from the EOS and the maximum-mass constraint. Finally, we study how the sound speed and the conformal anomaly are distributed inside neutron stars and show how these quantities depend on the imposed maximum-mass constraints.
