Merger and Postmerger of Binary Neutron Stars with a Quark-Hadron Crossover Equation of State
Merger and Postmerger of Binary Neutron Stars with a Quark-Hadron Crossover Equation of State
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具有夸克-强子交叉状态方程的双中子星的并合和并合后
DOI：
10.1103/physrevlett.129.181101
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发表时间：
2022
影响因子：
8.6
通讯作者：
Yi-Zhong Fan
中科院分区：
文献类型：
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作者：
Yong-Jia Huang;Luca Baiotti;Toru Kojo;Kentaro Takami;Hajime Sotani;Hajime Togashi;Tetsuo Hatsuda;Shigehiro Nagataki;Yi-Zhong Fan
首次研究了夸克-强子交叉(QHC)状态方程的全广义相对论双中子星(BNS)合并模拟。与具有纯强子物质或具有一阶夸克-强子相变(1PT)的状态方程不同，QHC状态方程在过渡区显示出声速峰值，并因此出现硬化。我们研究了这种僵化在合并和合并后引力(GW)信号中的影响。通过在二进制质量范围内的模拟，通过贝叶斯推理提取的合并后GW谱的主峰频率()因状态方程的不同而出现特征差异。特别是，我们发现：(I)对于质量较低的双星，由于合并后的最大重子数密度()保持在核物质密度()的3-4倍以下，在该密度范围内QHC模型的特征刚化导致比基础强子状态方程的计算结果低，从而也比具有1PT的状态方程的计算结果低；(Ii)对于质量较高的双星，可能会超过，这取决于EOS模型，QHC模型中的声速峰值是高还是低取决于声速峰值的高度。比较不同EOS和BNS质量的数值，为如何区分EOS高密度端不同类型的夸克动力学提供了重要线索，并与未来用第三代GW探测器进行的千赫GW观测有关。
Fully general-relativistic binary-neutron-star (BNS) merger simulations with quark-hadron crossover (QHC) equations of state (EOS) are studied for the first time. In contrast to EOS with purely hadronic matter or with a first-order quark-hadron phase transition (1PT), in the transition region QHC EOS show a peak in sound speed and thus a stiffening. We study the effects of such stiffening in the merger and postmerger gravitational (GW) signals. Through simulations in the binary-mass range, characteristic differences due to different EOS appear in the frequency of the main peak of the postmerger GW spectrum (), extracted through Bayesian inference. In particular, we found that (i) for lower-mass binaries, since the maximum baryon number density () after the merger stays below 3–4 times the nuclear-matter density (), the characteristic stiffening of the QHC models in that density range results in a lowerthan that computed for the underlying hadronic EOS and thus also than that for EOS with a 1PT; (ii) for higher-mass binaries, wheremay exceeddepending on the EOS model, whetherin QHC models is higher or lower than that in the underlying hadronic model depends on the height of the sound-speed peak. Comparing the values offor different EOS and BNS masses gives important clues on how to discriminate different types of quark dynamics in the high-density end of EOS and is relevant to future kilohertz GW observations with third-generation GW detectors.