论文标题
更换活跃的银河系核：超级质量黑洞的关闭二进制
Changing-look active galactic nuclei: close binaries of supermassive black holes in action
论文作者
论文摘要
更换活跃的银河系核（Cl-agns）作为一种新的亚种群挑战AGN的某些基本物理，因为该现象的时间表几乎不能与积聚磁盘模型相吻合。在这封信{\ textit {}}中，我们演示了极端情况：具有高偏心率的超大型黑洞（CB-SMBHS）的近距离二进制文件能够通过一个轨道触发CL跃迁。在这种情况下，二进制黑洞通过在Apastron阶段剥离电路磁盘的内部边缘来建立自己的迷你磁盘，此后，它们在periastron期间与磁盘在一个轨道时期内有效地交换了角动量。对于将逆行逆行旋转到轨道的迷你磁盘，潮汐扭矩将迷你磁盘的潮汐部分迅速挤压到半径较小的半径中，这会迅速导致更高的积聚和短片，然后磁盘下降到2型AGN中。序列化迷你磁盘从二进制中获得角动量并向外旋转，从而导致从Type-1型转换到2型。周围发生的旋转阶段发生。 CB-SMBHS控制周期1和2型之间具有轨道周期的跃迁，但允许Cl-AGN光曲线中的各种特性。
Changing-look active galactic nuclei (CL-AGNs) as a new subpopulation challenge some fundamental physics of AGNs because the timescales of the phenomenon can hardly be reconciled with accretion disk models. In this Letter{\textit{}}, we demonstrate the extreme case: close binaries of supermassive black holes (CB-SMBHs) with high eccentricities are able to trigger the CL transition through one orbit. In this scenario, binary black holes build up their own mini-disks by peeling gas off the inner edges of the circumbinary disk during the apastron phase, after which they tidally interact with the disks during the periastron phase to efficiently exchange angular momentum within one orbital period. For mini-disks rotating retrograde to the orbit, the tidal torque rapidly squeezes the tidal parts of the mini-disks into a much smaller radius, which rapidly results in higher accretion and short flares before the disks decline into type-2 AGNs. Prograde-rotation mini-disks gain angular momentum from the binary and rotate outward, which causes a rapid turn-off from type-1 to type-2. Turn-on occurs around the apastron phase. CB-SMBHs control cycle transitions between type-1 and type-2 with orbital periods but allow diverse properties in CL-AGN light curves.
