The formation mechanism of super star clusters (SSCs), a present-day analog of the ancient globulars, still remains elusive. The major merger, the Antennae galaxies is forming SSCs and is one of the primary targets to test the cluster formation mechanism. We reanalyzed the archival ALMA CO data of the Antennae and found three typical observational signatures of a cloud-cloud collision toward SSC B1 and other SSCs in the overlap region; i. two velocity components with $\sim$100 km s$^{-1}$ velocity separation, ii. the bridge features connecting the two components, and iii. the complementary spatial distribution between them, lending support for collisions of the two components as a cluster formation mechanism. We present a scenario that the two clouds with 100 km s$^{-1}$ velocity separation collided, and SSCs having $\sim$10$^6$-10$^7$ $M_{\rm \odot}$ were formed rapidly during the time scale. {We compared the present results with the recent studies of star forming regions in the Milky Way and the LMC, where the SSCs having $\sim$10$^4$-10$^5$ $M_{\rm \odot}$ are located. As a result, we found that there is a positive correlation between the compressed gas pressure generated by collisions and the total stellar mass of SSC, suggesting that the pressure may be a key parameter in the SSC formation.

中文翻译：

---

触角星系NGC 4038/NGC 4039中由云-云碰撞引发的年轻大质量星团的形成

超级星团（SSCs）的形成机制是古代球状星团的现代类似物，仍然难以捉摸。主要的合并，天线星系正在形成 SSC，是测试星团形成机制的主要目标之一。我们重新分析了天线的档案 ALMA CO 数据，发现了三个典型的云-云碰撞观测特征，即对重叠区域内的 SSC B1 和其他 SSC；一世。具有 $\sim$100 km s$^{-1}$ 速度分离的两个速度分量，ii。桥梁功能连接两个组件，和iii。它们之间互补的空间分布，支持作为集群形成机制的两个组件的碰撞。我们提出了一个场景，两个具有 100 公里 s$^{-1}$ 速度间隔的云相撞，和具有 $\sim$10$^6$-10$^7$ $M_{\rm \odot}$ 的 SSC 在时间尺度内迅速形成。{我们将目前的结果与最近对银河系和 LMC 中恒星形成区域的研究进行了比较，其中具有 $\sim$10$^4$-10$^5$$M_{\rm \odot}$ 的 SSCs 是位于。结果，我们发现碰撞产生的压缩气体压力与SSC的总恒星质量之间存在正相关，表明压力可能是SSC形成的关键参数。