论文标题
恒星簇中多个恒星种群的发作何时发生：没有证据表明NGC 419的主要化学变化显着变化
When does the onset of multiple stellar populations in star clusters occur-III: No evidence of significant chemical variations in main-sequence stars of NGC 419
论文作者
论文摘要
最近的研究表明，在星团中存在多个恒星种群（MPS）的开始年龄似乎与年轻群集中扩展的主要序列转弯（EMSTO）的消失相对应，这是一种与恒星旋转有关的模式。一个推测性的建议是，MP可能是由磁制动引起的，磁制动器是与旋转相关的恒星进化效应。在这项工作中，我们将年轻的大型群集NGC 419用作测试台。我们检查了其磁性烘烤的MS恒星是否会展示MPS。使用通过哈勃太空望远镜观察到的深紫外图和可见图像，并结合对氮（N）丰度敏感的特定颜色指数，我们检查了其晚期G-和K型MS恒星是否受N变化的影响。我们的分析报告说，其GK型MS的形态很可能是SSP，并且只有可忽略的概率表明存在最高0.4 dex的N变化。我们得出的结论是，其GK型MS恒星之间没有显着的N变化。晚期MS恒星之间没有明显的化学变化，表明MP可能不是磁性刹车恒星的特定模式。
Recent studies have revealed that the onset age for the presence of multiple stellar populations (MPs) in star clusters seems to correspond to the disappearance of the extended main-sequence turnoff (eMSTO) in young clusters, a pattern associated with stellar rotations. A speculative suggestion is that MPs might be caused by the magnetic brake, a stellar evolutionary effect linked to the rotation. In this work, we use the young massive cluster NGC 419 as a testbed. We examined if its magnetically baked MS stars would exhibit MPs. Using the deep ultraviolet and visible images observed through the Hubble Space Telescope, combined with a specific color index that is sensitive to the nitrogen (N) abundance, we examined if its late G- and K-type MS stars are affected by N variation. Our analysis reports that the morphology of its GK-type MS is most likely an SSP, and only a negligible probability that indicates a N variation up to 0.4 dex is present. We conclude that there is no significant N variation among its GK-type MS stars. The absence of a significant chemical variation among the late-type MS stars indicates that MPs might not be a specific pattern of magnetically braked stars.
