论文标题
认识父母：E1821+643中超级质量黑洞候选者的祖细胞二进制
Meet the parents: the progenitor binary for the supermassive black hole candidate in E1821+643
论文作者
论文摘要
由于引力波的各向异性发射，二进制黑洞合并的残余合并可以得到高达$ 5,000 \ text {km s $^{ - 1} $} $的后坐力。 E1821+643是一个以$ \ sim 2,100 \ text {km s $^{ - 1} $} $移动的超级大质量黑洞，沿着与主机银河相关的视线。这表明$ \ sim 2,240 \ text {km s $^{ - 1} $} $的后坐力踢。这样的踢足够强大，可以从其$ m_ \ text {gal} \ sim 2 \ times 10^{12} \ text {m} _ {\ odot} $ host galaxy弹出E1821+643。在这项工作中，我们解决了一个问题：形成E1821+643的祖细胞二进制的可能属性是什么？使用天体物理动机的先验，我们推断出E1821+643可能是由二进制黑洞系统形成的，其质量为$ M_1 \ sim 1.9^{+5.0} _ { - 3.8} \ times 10^{9} {9} \ text {m} 8.1^{+3.9} _ { - 3.2} \ times 10^{8} \ text {m} _ {\ odot} $（90 \％可信间隔）。该二进制中的黑洞可能会以$χ_1= 0.87^{+0.11} _ { - 0.26} $，$χ_2= 0.77^{+0.19} _ { - 0.37} $的无量纲旋转幅度迅速旋转。对于与轨道角动量轴对齐的旋转不可能是这样的高后坐力速度。这表明E1821+643在热气中合并，这被认为提供了一个环境，使积聚的自旋比对相对于合并时间表缓慢进行。我们推断E1821+643可能会以无量纲自旋$χ= 0.92 \ pm0.04 $迅速旋转。 A $2.6 \times 10^9 \text{ M}_{\odot}$ black hole, recoiling from a gas-rich environment at $v\sim 2,240\text{ km s$^{-1}$}$ is likely to persist as an active galactic nuclei for $\sim 860$ Myr, in which time it traverses $\sim 2$ Mpc.
The remnants of binary black hole mergers can be given recoil kick velocities up to $5,000\text{ km s$^{-1}$}$ due to anisotropic emission of gravitational waves. E1821+643 is a recoiling supermassive black hole moving at $\sim 2,100\text{ km s$^{-1}$}$ along the line-of-sight relative to its host galaxy. This suggests a recoil kick of $\sim 2,240\text{ km s$^{-1}$}$. Such a kick is powerful enough to eject E1821+643 from its $M_\text{gal}\sim 2 \times 10^{12}\text{ M}_{\odot}$ host galaxy. In this work, we address the question: what are the likely properties of the progenitor binary that formed E1821+643? Using astrophysically motivated priors, we infer that E1821+643 was likely formed from a binary black hole system with masses of $m_1\sim 1.9^{+5.0}_{-3.8}\times 10^{9}\text{ M}_{\odot}$, $m_2\sim 8.1^{+3.9}_{-3.2} \times 10^{8}\text{ M}_{\odot}$ (90\% credible intervals). The black holes in this binary were likely to be spinning rapidly with dimensionless spin magnitudes of $χ_1 = 0.87^{+0.11}_{-0.26}$, $χ_2 = 0.77^{+0.19}_{-0.37}$. Such a high recoil velocity is impossible for spins aligned to the orbital angular momentum axis. This suggest that E1821+643 merged in hot gas, which is thought to provide an environment where spin alignment from accretion proceeds slowly relative to the merger timescale. We infer that E1821+643 is likely to be rapidly rotating with dimensionless spin $χ = 0.92\pm0.04$. A $2.6 \times 10^9 \text{ M}_{\odot}$ black hole, recoiling from a gas-rich environment at $v\sim 2,240\text{ km s$^{-1}$}$ is likely to persist as an active galactic nuclei for $\sim 860$ Myr, in which time it traverses $\sim 2$ Mpc.
