On the population III binary black hole mergers beyond the pair-instability mass gap
On the population III binary black hole mergers beyond the pair-instability mass gap
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DOI：
10.1093/mnrasl/slab052
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发表时间：
2021-04
影响因子：
2.6
通讯作者：
K. Hijikawa;A. Tanikawa;T. Kinugawa;T. Yoshida;H. Umeda
中科院分区：
文献类型：
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作者：
K. Hijikawa;A. Tanikawa;T. Kinugawa;T. Yoshida;H. Umeda
我们执行包含非常大的种群(Pop.)的二进制种群合成计算。III恒星高度达1500米，并研究双星黑洞(BBH)合并的性质。在对不稳定性质量隙上方，我们发现典型的初级黑洞(BH)质量为135-340M。原始黑洞的最大质量可达686M。两个组分都在质量隙以上的BBH具有低的有效激发自旋∼0。到目前为止，还没有探测到超过质量间隙的BBH合并，并得到了合并率密度的上限。如果Pop的初始质量函数(IMF)。将III星简单地表示为ξm(M)∝m−α(一次幂定律)，我们发现要使合并率密度不超过上限，需要α&2.8。未来，爱因斯坦望远镜和Pre-DECIGO等引力波探测器将以高红移观测到BBH合并。我们建议，我们或许能够对流行音乐施加严格的限制。III IMF将未来观测得到的合并率密度与理论得出的合并率密度进行比较。
We perform a binary population synthesis calculation incorporating very massive population (Pop.) III stars up to 1500 M , and investigate the nature of binary black hole (BBH) mergers. Above the pair-instability mass gap, we find that the typical primary black hole (BH) mass is 135–340 M . The maximum primary BH mass is as massive as 686 M . The BBHs with both of their components above the mass gap have low effective inspiral spin ∼ 0. So far, no conclusive BBH merger beyond the mass gap has been detected, and the upper limit on the merger rate density is obtained. If the initial mass function (IMF) of Pop. III stars is simply expressed as ξm (m) ∝ m−α (single power law), we find that α & 2.8 is needed in order for the merger rate density not to exceed the upper limit. In the future, the gravitational wave detectors such as Einstein telescope and Pre-DECIGO will observe BBH mergers at high redshift. We suggest that we may be able to impose a stringent limit on the Pop. III IMF by comparing the merger rate density obtained from future observations with that derived theoretically.