论文标题
核恒星簇中的失控碰撞全球不稳定：大规模黑洞形成路线的数值测试
Global instability by runaway collisions in nuclear stellar clusters: Numerical tests of a route for massive black hole formation
论文作者
论文摘要
星系中心设有核恒星簇，超大型黑洞或两者兼而有之。这种二分法的起源仍然是一个谜。核恒星簇是宇宙中最密集的恒星系统，因此它们是发生失控碰撞的理想场所。先前的研究提出了在此类集群中可能存在临界质量尺度的，为此，碰撞的发生变得非常频繁，并导致形成非常庞大的物体。尽管很难通过模拟直接探测这种情况，但我们在这里旨在使用玩具模型来证明概念的证明，在这些模型中，基于简化的紧凑型系统显示了这种过渡的发生，在这种情况下，典型的演变时间尺度将比真实的世界比较更快。确实，我们的模拟证实了这种过渡发生的，并且高达50％的群集质量可以进入临界质量尺度高于临界质量的群集的中心大体物体的形成。因此，我们的结果基于理想化的模拟支持了拟议的新方案。对观察到的核星簇的初步分析显示，与我们的模拟中的临界质量相关的趋势相似。我们进一步讨论了在实际核星团中应用拟议方案的注意事项。
The centres of galaxies host nuclear stellar clusters, supermassive black holes, or both. The origin of this dichotomy is still a mystery. Nuclear stellar clusters are the densest stellar system in the Universe, so they are ideal places for runaway collisions to occur. Previous studies have proposed the possible existence of a critical mass scale in such clusters, for which the occurrence of collisions becomes very frequent and leads to the formation of a very massive object. While it is difficult to directly probe this scenario with simulations, we here aim for a proof of concept using toy models where the occurrence of such a transition is shown based on simplified compact systems, where the typical evolution time-scales will be faster compared to the real Universe. Indeed our simulations confirm that such a transition takes place and that up to 50 per cent of the cluster mass can go into the formation of a central massive object for clusters that are above the critical mass scale. Our results thus support the proposed new scenario on the basis of idealized simulations. A preliminary analysis of observed nuclear star clusters shows similar trends related to the critical mass as in our simulations. We further discuss the caveats for the application of the proposed scenario in real nuclear star clusters.
