论文标题
银河系球形簇：彼此的近距离接触率和中央超级黑洞
Milky Way Globular Clusters: close encounter rates with each other and with the Central Supermassive Black Hole
论文作者
论文摘要
使用GAIA（ESA）数据版本2的数据，我们进行了银河系的球状簇（GC）的轨道计算。为了探索GCS之间可能的碰撞，使用我们开发的高级ϕ葡萄代码，我们集成了（向后和向前）119个具有可靠位置和适当运动的对象的轨道。在计算中，我们采用了逼真的轴对称银河电位（Bulge + Disk + Halo）。在使用不同的影响条件下，我们发现了可能发生冲突的五对GC：Terzan 3 -NGC 6553，Terzan 3 -NGC 6218，Liller 1 -NGC 6522，Djorg 2 -NGC 6552和NGC 6552和NGC 6355 -NGC 6637。假设它们之间的最大PC距离标准，我们估计有11个紧密遭遇事件。从我们的数值模拟中，我们将密切相互作用速率至少为每个GYR，而影响参数小于30 pc；每天有一个事件，影响参数小于60 pc。我们的计算表明，NGC 6121的一次非常紧密的相遇，中央SMBH接近5.5 PC（实际上是直接碰撞）。根据对我们选择的11 GC的可能祖细胞的扩展文献搜索，我们发现其中大多数具有银河系主要凸起起源。
Using the data from Gaia (ESA) Data Release 2 we performed the orbital calculations of globular clusters (GCs) of the Milky Way. To explore possible collisions between the GCs, using our developed highorder ϕ-GRAPE code, we integrated (backwards and forward) the orbits of 119 objects with reliable positions and proper motions. In calculations, we adopted a realistic axisymmetric Galactic potential (bulge + disk + halo). Using different impact conditions, we found five pairs of the GCs that likely experienced collisions: Terzan 3 - NGC 6553, Terzan 3 - NGC 6218, Liller 1 - NGC 6522, Djorg 2 - NGC 6552 and NGC 6355 - NGC 6637. We analyzed the GCs interaction rates with the central supermassive black hole. Assuming the maximum 100 pc distance criteria for separation between them we estimated 11 close encounter events. From our numerical simulations, we estimate the close interaction rate as at least one event per Gyr with the impact parameter less than 30 pc; and one event per Myr with the impact parameter less than 60 pc. Our calculations show one very close encounter of NGC 6121 with the central SMBH near 5.5 pc (practically direct collision). Based on the extended literature search for the possible progenitor of our selected 11 GCs, we found that most of them have a Milky Way main bulge origin.
