论文标题
AGN吸积盘中的二进制黑洞合并：重力波速率密度估计值
Binary black hole mergers in AGN accretion discs: gravitational wave rate density estimates
论文作者
论文摘要
Ligo/处女座迄今检测到的大多数重力波（GW）事件源自二进制黑洞（BBH）合并。在不同的二元演化路径中，BBH在活性银河核（AGN）的积聚盘中的合并是GW检测的可能来源。我们考虑了嵌入AGN积聚盘中BBH的轨道演化的理想分析模型。在此框架中，二元相互作用增加了轨道偏心率并降低了轨道分离，将BBH推向了GW发射最终导致合并的状态。我们根据AGN积聚盘中径向分布的BBHS群体的合并时间表的加权平均值来计算该通道的GW合并速率密度。预测的合并费率广义在于$ \ Mathcal {r} \ sim（0.002-18）\，\ Mathrm {gpc^{ - 3} yr^{ - 1}} $。我们分析了合并速率密度对积聚盘和二元轨道参数的依赖性，强调了轨道偏心率的重要作用。我们在更广泛的二元演化场景中讨论了这种特定的BBH-In-In-In-In-In-In-In-In-In-In-In-In-In-In-In-In-In-In-In-In-In-In-In-In-In-AGN形成含义。
The majority of gravitational wave (GW) events detected so far by LIGO/Virgo originate from binary black hole (BBH) mergers. Among the different binary evolution paths, the merger of BBHs in accretion discs of active galactic nuclei (AGNs) is a possible source of GW detections. We consider an idealised analytical model of the orbital evolution of BBHs embedded in an AGN accretion disc. In this framework, the disc-binary interaction increases the orbital eccentricity and decreases the orbital separation, driving the BBH into a regime where GW emission eventually leads to coalescence. We compute the resulting GW merger rate density from this channel based on a weighted average of the merger timescales of a population of BBHs radially distributed within the AGN accretion disc. The predicted merger rates broadly lie in the range $\mathcal{R} \sim (0.002 - 18) \, \mathrm{Gpc^{-3} yr^{-1}}$. We analyse the dependence of the merger rate density on both the accretion disc and binary orbital parameters, emphasising the important role of the orbital eccentricity. We discuss the astrophysical implications of this particular BBH-in-AGN formation channel in the broader context of binary evolution scenarios.
