论文标题
二进制黑洞的旋转分布估计黑洞踢的偏见
Biases in estimates of black hole kicks from the spin distribution of binary black holes
论文作者
论文摘要
现在已经观察到了50多个二元黑洞合并的人口，这是Ligo和处女座重力波观测站观察到的。虽然已知中子恒星在超新星出生时具有与冲动的踢球相关的较大速度，但无论黑洞是否会受到类似的踢球，而且幅度是什么，仍然是一个悬而未决的问题。最近，Callister等人。 （2021）在假设中分析了二进制黑洞的种群，即它们都是通过孤立的二元进化形成的，并声称大型黑洞踢（以99％的置信度大于260 km/s）是合并二元黑洞以匹配观察结果的自旋分布所必需的。在这里，我们强调了Callister等人做出的关键假设。 （2021） - 所有次要黑洞都可以潮湿 - 并不是由物理模型激发，并且可能导致其对黑洞踢球大小的估计。我们只对Callister等人进行了微小的更改。 （2021）模型，考虑到潮汐同步无效的更广泛合并二进制文件。我们表明，这自然会产生二次黑洞的双峰自旋分布，并且可以通过更典型的100 km/s的黑洞踢来解释二进制黑洞种群中观察到的自旋轨道未对准，这与含有黑色黑洞的银河X射线二进制室推断出的踢脚一致。我们得出的结论是，大多数二元黑洞人口与通过孤立的二元进化形成一致。
A population of more than 50 binary black hole mergers has now been observed by the LIGO and Virgo gravitational-wave observatories. While neutron stars are known to have large velocities associated with impulsive kicks imparted to them at birth in supernovae, whether black holes receive similar kicks, and of what magnitude, remains an open question. Recently, Callister et al. (2021) analysed the binary black hole population under the hypothesis that they were all formed through isolated binary evolution and claimed that large black hole kicks (greater than 260 km/s at 99% confidence) were required for the spin distribution of merging binary black holes to match observations. Here we highlight that a key assumption made by Callister et al. (2021) -- that all secondary black holes can be tidally spun up -- is not motivated by physical models, and may lead to a bias in their estimate of the magnitudes of black hole kicks. We make only minor changes to the Callister et al. (2021) model, accounting for a population of wider merging binaries where tidal synchronisation is ineffective. We show that this naturally produces a bimodal spin distribution for secondary black holes, and that the spin-orbit misalignments observed in the binary black hole population can be explained by more typical black hole kicks of order 100 km/s, consistent with kicks inferred from Galactic X-ray binaries containing black holes. We conclude that the majority of the binary black hole population is consistent with forming through isolated binary evolution.
