AI 中文总结
该研究通过半解析估计与数值模拟，揭示大质量黑洞周围的大质量吸积盘可通过希尔斯机制驱动双星瓦解，银河系中心星盘曾引发约100次此类事件，或能解释S星族与超高速恒星的起源。
AI 中文摘要
银心区域大质量黑洞（MBH）周围的吸积盘可包含显著质量，此时其非球形势会对绕MBH运行的单星和双星施加显著力矩，这些力矩可使轨道偏心率变得极高。此前研究表明，这种驱动会导致单星被MBH的潮汐引力瓦解。本文中，我们表征了这些力矩通过希尔斯（Hills）机制驱动双星至瓦解点的能力，推导了由银心区域普通吸积盘驱动的双星瓦解数量的半解析估计值，该估计值已通过数值模拟验证。利用这些结果，我们估计银河系中心约5百万年星盘的形成驱动了约100次双星瓦解的爆发，这些瓦解产生了过量的S星族恒星和超高速恒星，其中可能包括目前已知最快的超高速恒星S5-HVS1。在其他星系中，该过程产生的S星族恒星类似物可能在经历吸积盘阶段后演化成潮汐瓦解事件。超高速恒星观测或有助于明确吸积盘驱动瓦解的重要性，这类瓦解近乎各向同性地抛射恒星且呈时间上的爆发形式，在驱动双星瓦解的各类过程中具有独特组合。
英文摘要
Accretion disks around massive black holes (MBHs) in galactic nuclei can contain significant mass, in which case their non-spherical potentials exert significant torques on single and binary stars orbiting the MBHs. These torques can drive orbits to very large eccentricities. Previous works have shown that this driving can cause disruptions of single stars by the tidal gravity of the MBH. Here, we characterize the ability of these torques to drive binary stars to the point of disruption via the Hills mechanism. We derive semi-analytical estimates, validated with numerical simulations, of the number of binary disruptions driven by a generic disk in a generic nucleus. Using these results, we estimate that the formation of the ~5-Myr-old disk of stars in the Galactic Center drove a burst of ~10^2 binary disruptions. These disruptions produced an excess of S-cluster stars and hypervelocity stars --- possibly including S5-HVS1, the fastest-known hypervelocity star. In other galaxies, analogues of S-cluster stars produced by this process may evolve into tidal disruption events following a disk phase. Hypervelocity star observations may help clarify the importance of disk-driven disruptions, which eject stars nearly isotropically and in temporal bursts --- a unique combination among processes driving binary disruptions.
Comments16 pages, 11 figures (main text) + 8 pages, 2 figures (appendices). To be submitted to AAS Journals. Comments welcome!
