论文标题
失控的星星伪装成银河郊区的明星形成
Runaway stars masquerading as star formation in galactic outskirts
论文作者
论文摘要
在附近螺旋星系的郊外，在极低的气体表面密度中观察到恒星形成。在这些区域中，星际培养基以弥漫性原子氢为主的恒星形成很难用经典的恒星形成理论来解释。在这封信中，我们介绍了失控的星星，以解释这一观察结果。由年轻恒星集群中的碰撞动力制作的失控明星可以在其主要层次的一生中旅行。使用银河尺度的流体动力学模拟，包括对单个恒星的处理，我们证明了这种机制使年轻的大型恒星射入气体不足以触发恒星形成的环境中。这导致在不可能的地区出现恒星形成。我们得出的结论是，失控的恒星是对螺旋星系郊区恒星形成的观察的贡献，即使不是主导的因素。
In the outskirts of nearby spiral galaxies, star formation is observed in extremely low gas surface densities. Star formation in these regions, where the interstellar medium is dominated by diffuse atomic hydrogen, is difficult to explain with classic star formation theories. In this letter, we introduce runaway stars as an explanation for this observation. Runaway stars, produced by collisional dynamics in young stellar clusters, can travel kiloparsecs during their main-sequence lifetime. Using galactic-scale hydrodynamic simulations including a treatment of individual stars, we demonstrate that this mechanism enables the ejection of young massive stars into environments where the gas is not dense enough to trigger star formation. This results in the appearance of star formation in regions where it ought to be impossible. We conclude that runaway stars are a contributing, if not dominant, factor to the observations of star formation in the outskirts of spiral galaxies.
