Mapping of Milky Way Cepheid Variables

银河系造父变星绘图

• 批准号: 1945519
• 金额: --
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1945519
• 关键词: Mapping; Milky; Way; Cepheid; Variables

Cepheid Variables are young stars that physically pulsate causing a variation in their luminosity over time. An intrinsic relation exists between the period of these pulsations and the luminosity of these stars. They have therefore become vital distance indicators. Their young age implies they should mostly be found within the galactic disk. Any outliers would be of interest to merging history of the Milky Way: dwarf satellite galaxies interacting and colliding with our galaxy. Such events could throw the young Cepheids out of the disk to higher latitudes. The current Gaia DR1 data and the future DR2 release do no contain any time domain information of the cepheids contained within. Therefore, other selection criteria is needed to identify these stars in the data. This causes issues of contamination from other stellar types. Work in this project seeks to formulate optimal selection criteria to map the Cepheids and then devise theoretical models to explain how the observed distribution could have formed. Such work could be combined with the previous mappings of RR Lyrae variables to identify substructure within our Galaxy.

造父变星是年轻恒星的物理脉动，导致它们的光度随时间发生变化。这些脉动的周期和这些恒星的光度之间存在着内在的联系。因此，它们已成为至关重要的距离指标。它们的年轻意味着它们应该主要在银盘内被发现。任何离群值都将对合并银河系的历史感兴趣：矮小卫星星系与我们的星系相互作用和碰撞。这样的事件可能会把年轻的造父变星抛出圆盘，送到更高的纬度。当前的Gaia DR1数据和未来的DR2版本不包含包含在其中的头目的任何时域信息。因此，需要其他选择标准来识别数据中的这些恒星。这导致了来自其他恒星类型的污染问题。这个项目的工作是制定最佳的选择标准来绘制造父变星的地图，然后设计理论模型来解释观测到的分布是如何形成的。这项工作可以与天琴座RR变星之前的映射相结合，以确定我们银河系内的子结构。