Black Hole Mergers from an Evolving Population of Globular Clusters.
Black Hole Mergers from an Evolving Population of Globular Clusters.
复制标题
不断演化的球状星团群中的黑洞合并。
DOI：
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复制
发表时间：
2018
影响因子：
8.6
通讯作者：
B. Kocsis
中科院分区：
文献类型：
--
作者：
G. Fragione;B. Kocsis
LIGO/Virgo 检测到的高黑洞 (BH) 合并率引发了对其天体物理起源的质疑。一种可能性是动态通道，其中二元形成和硬化是由球状星团（GC）中的动态相遇催化的。先前的研究表明，当今宇宙中 GC 密度的 BH 合并率低于观测到的率。在这封信中，我们通过首次解释主星系内 GC 的演化来研究 BH 合并率。 GC 中的质量最初大约是原来的 8 倍，但由于蒸发和潮汐破坏而降至目前的值。许多在合并之前很久就被驱逐的 BH 双星起源于不再存在的 GC。我们发现，在红移 z=0.5 到 2 之间，GC 动态通道中的同动合并率在 18 到 35 Gpc^{-3} yr^{-1} 之间变化，在 z=0.5、1 和 2 范围内，总速率分别为每天 1、5、24 个事件。相对于孤立星团，宇宙演化和 GC 的破坏系统性地将当前的合并率提高了约 2 倍。引力波探测器网络提供了一种独特的观测探针，可观测 GC 群体的初始数量及其随后在整个宇宙时间内的演化。
The high rate of black hole (BH) mergers detected by LIGO/Virgo opened questions on their astrophysical origin. One possibility is the dynamical channel, in which binary formation and hardening is catalyzed by dynamical encounters in globular clusters (GCs). Previous studies have shown that the BH merger rate from the present day GC density in the Universe is lower than the observed rate. In this Letter, we study the BH merger rate by accounting for the first time for the evolution of GCs within their host galaxies. The mass in GCs was initially ∼8×higher, which decreased to its present value due to evaporation and tidal disruption. Many BH binaries that were ejected long before their merger originated in GCs that no longer exist. We find that the comoving merger rate in the dynamical channel from GCs varies between 18 to 35 Gpc^{-3} yr^{-1} between redshift z=0.5 to 2, and the total rate is 1, 5, 24 events per day within z=0.5, 1, and 2, respectively. The cosmic evolution and disruption of GCs systematically increases the present-day merger rate by a factor ∼2 relative to isolated clusters. Gravitational wave detector networks offer an unique observational probe of the initial number of GC populations and their subsequent evolution across cosmic time.
DOI：
10.3847/1538-4357/aaafce
发表时间：
2017-06
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Bao-Minh Hoang;S. Naoz;B. Kocsis;F. Rasio;F. Dosopoulou
通讯作者：
Bao-Minh Hoang;S. Naoz;B. Kocsis;F. Rasio;F. Dosopoulou
DOI：
10.3847/2041-8213/aad800
发表时间：
2018-05
期刊：
The Astrophysical Journal Letters
影响因子：
--
作者：
M. Fishbach;D. Holz;W. Farr
通讯作者：
M. Fishbach;D. Holz;W. Farr