Fully General Relativistic Simulations of Black Hole-Neutron Star Mergers
Fully General Relativistic Simulations of Black Hole-Neutron Star Mergers
复制标题
黑洞-中子星合并的完全广义相对论模拟
DOI：
10.1103/physrevd.77.084002
复制
发表时间：
2007
影响因子：
5
通讯作者：
T. Baumgarte
中科院分区：
文献类型：
--
作者：
Z. Etienne;J. Faber;Yuk Tung Liu;S. Shapiro;K. Taniguchi;T. Baumgarte
黑洞-中子星(BHNS)双星有望成为地面探测器可观测到的引力波的主要来源之一，也可能是短硬伽马射线暴(SGRBs)的前身。我们讨论了BHNS双星合并的新的完全广义相对论计算，它使用高精度、低偏心、共形的薄三明治构型作为初始数据。我们的演化是使用移动穿刺法进行的，并包括完全相对论的、高分辨率的激波捕获流体动力学处理。针对中子星不旋转、黑洞质量比为3：1的非自转系统，我们研究了该系统中的激旋、合并和盘的形成。我们发现，绝大多数物质被迅速吸积，中子星静止质量的不超过3%被抛入一个稀薄的、受引力约束的圆盘。对于质量比为2比1和1比1的中子星，我们得到了类似的结果，即使我们在2比1质量比的情况下减少了中子星的压缩。这些周围的圆盘达到了适合触发SGRBs的温度，但它们的质量可能太小，无法产生所需的总能量输出。我们测量引力波形并计算频率空间中的有效应力，发现我们的波形与高级LIGO波段内的双星黑洞合并产生的波形之间存在可测量的差异。这些差异出现的频率对应于当NS被黑洞潮汐破坏和吸积时发生的发射。由此得到的关于中子星半径的信息可用于约束中子星的状态方程。
Black hole-neutron star (BHNS) binaries are expected to be among the leading sources of gravitational waves observable by ground-based detectors, and may be the progenitors of short-hard gamma-ray bursts (SGRBs) as well. We discuss our new fully general relativistic calculations of merging BHNS binaries, which use high-accuracy, low-eccentricity, conformal thin-sandwich configurations as initial data. Our evolutions are performed using the moving puncture method and include a fully relativistic, high-resolution shock-capturing hydrodynamics treatment. Focusing on systems in which the neutron star is irrotational and the black hole is nonspinning with a 3 ratio 1 mass ratio, we investigate the inspiral, merger, and disk formation in the system. We find that the vast majority of material is promptly accreted and no more than 3% of the neutron star's rest mass is ejected into a tenuous, gravitationally bound disk. We find similar results for mass ratios of 2 ratio 1 and 1 ratio 1, even when we reduce the neutron stars (NS) compaction in the 2 ratio 1 mass ratio case. These ambient disks reach temperatures suitable for triggering SGRBs, but their masses may be too small to produce the required total energy output. We measure gravitational waveforms and compute the effective strainmore » in frequency space, finding measurable differences between our waveforms and those produced by binary black hole mergers within the advanced LIGO band. These differences appear at frequencies corresponding to the emission that occurs when the NS is tidally disrupted and accreted by the black hole. The resulting information about the radius of the neutron star may be used to constrain the neutron star equation of state.« less
影响因子：
8.6
作者：
José A. González;U. Sperhake;B. Brügmann;M. Hannam;S. Husa
通讯作者：
José A. González;U. Sperhake;B. Brügmann;M. Hannam;S. Husa