论文标题
活跃银核中的偏心黑洞合并
Eccentric Black Hole Mergers in Active Galactic Nuclei
论文作者
论文摘要
引力波（GW）瞬变的天体物理起源是Ligo/处女座发现之后的及时开放问题。在活跃的银河核（AGN）中，二进制形成并通过与密集的恒星和气态AGN磁盘相互作用而有效地进化。先前的研究表明，在这种环境中，恒星质量的黑洞（BH）合并可以解释Ligo/Pirgo观察到的合并率和可疑分层合并的数量。二进制偏心分布可以提供进一步的信息，以区分天体物理模型。在这里，我们得出了AGN磁盘中BH合并的偏心分布。我们发现，偏心率主要是由于二进制（BS）相互作用，这导致大多数BH合并在AGN磁盘中具有明显的偏心率，$ 0.01 \，\ Mathrm {Hz} $，可通过LISA检测到。如果BS相互作用发生在各向同性3D方向上，则$ 8 $ - $ 30 \％$ $的AGN磁盘合并的偏心将以$ 10 \，\ Mathrm {hz} $上的$ 10 \ $ e_ {10 \，\ rm hz} $ hz} $ hz} \ gtrsim 0.03 $/$ kaig/vir ligo/ivogo，n lig kagra，合并的$ e_ {10 \，\ rm hz} \ geq 0.3 $。另一方面，如果BS互动由于磁盘上的扭矩而局限于AGN磁盘飞机，每次互动期间具有1-20个中间二进制状态，或者BHS可以从中央级别的Black Hole中迁移到$ \ simsim10^{ - 3} \，\ Mathrm {PC} $，然后是$ 70 $ - $ 70 $ 70 $ $ 70 $ $ 70 $ $ 70。 （$ e_ {10 \，\ rm hz} \ geq 0.3 $），与GW190521中可能的高偏眼相一致。
The astrophysical origin of gravitational wave (GW) transients is a timely open question in the wake of discoveries by LIGO/Virgo. In active galactic nuclei (AGNs), binaries form and evolve efficiently by interaction with a dense population of stars and the gaseous AGN disk. Previous studies have shown that stellar-mass black hole (BH) mergers in such environments can explain the merger rate and the number of suspected hierarchical mergers observed by LIGO/Virgo. The binary eccentricity distribution can provide further information to distinguish between astrophysical models. Here we derive the eccentricity distribution of BH mergers in AGN disks. We find that eccentricity is mainly due to binary-single (BS) interactions, which lead to most BH mergers in AGN disks having a significant eccentricity at $0.01\,\mathrm{Hz}$, detectable by LISA. If BS interactions occur in isotropic-3D directions, then $8$--$30\%$ of the mergers in AGN disks will have eccentricities at $10\,\mathrm{Hz}$ above $e_{10\,\rm Hz}\gtrsim 0.03$, detectable by LIGO/Virgo/KAGRA, while $5$--$17\%$ of mergers have $e_{10\,\rm Hz}\geq 0.3$. On the other hand, if BS interactions are confined to the AGN-disk plane due to torques from the disk, with 1-20 intermediate binary states during each interaction, or if BHs can migrate to $\lesssim10^{-3}\,\mathrm{pc}$ from the central supermassive black hole, then $10$--$70\%$ of the mergers will be highly eccentric ($e_{10\,\rm Hz} \geq 0.3$), consistent with the possible high eccentricity in GW190521.
