Orbital Migration of Interacting Stellar Mass Black Holes in Disks around Supermassive Black Holes. II. Spins and Incoming Objects
Orbital Migration of Interacting Stellar Mass Black Holes in Disks around Supermassive Black Holes. II. Spins and Incoming Objects
复制标题
DOI：
10.3847/1538-4357/abbc1d
复制
发表时间：
2018-07
期刊：
影响因子：
--
通讯作者：
Amy Secunda;J. Bellovary;M. Mac Low;K. Ford;B. McKernan;N. W. C. Leigh;W. Lyra;Z. Sándor;J. A
中科院分区：
文献类型：
--
作者：
Amy Secunda;J. Bellovary;M. Mac Low;K. Ford;B. McKernan;N. W. C. Leigh;W. Lyra;Z. Sándor;J. A
aLIGO 和 Virgo 检测到的合并恒星质量双黑洞 (BBH) 的质量、速率和自旋给传统的 BBH 形成和合并场景带来了挑战。活动星系核（AGN）盘提供了一个有希望的额外合并通道，因为气体的强大影响力驱动轨道演化，使相遇耗散，并导致迁移。先前的研究表明，活动星系核盘中的恒星质量黑洞（sBH）会迁移到盘中被称为迁移陷阱的区域，其中正负气体扭矩相互抵消，从而导致频繁的 BBH 形成。在这里，我们通过模拟通过迁移或倾斜减少进入内盘的额外 sBH 的演化来建立这项工作。我们还检查了模型中形成的 BBH 是否具有围绕其质心相对于圆盘的逆行或顺行轨道，从而确定了合并的 BBH 相对于圆盘的自旋方向。进入内盘的轨道飞行器在迁移陷阱附近的共振轨道上形成 BBH 和 sBH。当这些 sBH 达到 ≳80 M☉ 时，它们与迁移陷阱中的 sBH 形成 BBH，在 10 Myr 上达到~1000 M☉。我们发现模拟轨道中 68% 的 BBH 处于逆行方向，这意味着合并通道中的 BBH 将具有小的无量纲对齐自旋 χeff。总体而言，我们的模型产生的 BBH 类似于迄今为止检测到的大多数 BBH 合并 (0.66–120 Gpc−3 yr−1) 和最近的两个异常检测，GW190412 (∼0.3 Gpc−3 yr−1) 和 GW190521 (∼0.1 Gpc−3 yr−1)。
The masses, rates, and spins of merging stellar mass binary black holes (BBHs) detected by aLIGO and Virgo provide challenges to traditional BBH formation and merger scenarios. An active galactic nucleus (AGN) disk provides a promising additional merger channel because of the powerful influence of the gas that drives orbital evolution, makes encounters dissipative, and leads to migration. Previous work showed that stellar mass black holes (sBHs) in an AGN disk migrate to regions of the disk, known as migration traps, where positive and negative gas torques cancel out, leading to frequent BBH formation. Here we build on that work by simulating the evolution of additional sBHs that enter the inner disk by either migration or inclination reduction. We also examine whether the BBHs formed in our models have retrograde or prograde orbits around their centers of mass with respect to the disk, determining the orientation of the spin of the merged BBHs relative to the disk. Orbiters entering the inner disk form BBHs with sBHs on resonant orbits near the migration trap. When these sBHs reach ≳80 M☉, they form BBHs with sBHs in the migration trap, which reach ∼1000 M☉ over 10 Myr. We find 68% of the BBHs in our simulation orbit in the retrograde direction, which implies that BBHs in our merger channel will have small dimensionless aligned spins, χeff. Overall, our models produce BBHs that resemble both the majority of BBH mergers detected thus far (0.66–120 Gpc−3 yr−1) and two recent unusual detections, GW190412 (∼0.3 Gpc−3 yr−1) and GW190521 (∼0.1 Gpc−3 yr−1).