RUI: The BRAVA-RR Survey: uncovering an ancient Spheroidal Bulge in the Milky Way

研究人员将观察一类特殊的老恒星，称为天琴座RR星，位于银河系的中心。 研究这些恒星可以让我们一窥银河系是如何随着时间而变化的。 研究人员将观察这些恒星的大量样本，以重建它们在空间中的运动。 然后，重建的运动将使研究人员能够区分哪些RR型天琴座恒星是银河系中心周围的晕、盘或“球状隆起”的一部分。 这些测量将有助于更好地了解银河系形成的早期阶段。 调查人员将招募合格的学生，针对科学，技术，工程和数学（STEM）学科中的第一代和其他代表性不足的学生。 这些学生研究人员将从望远镜收集数据，分析数据，并在会议上提出。调查员将继续领导大众科学咖啡馆系列，组织星星派对，并与当地男孩女孩俱乐部合作，吸引当地社区的参与。调查员将使用天琴座RR星作为测试探针，研究内星系的形成。 使用这些古老而缺乏金属的恒星是很重要的，因为大多数用于了解银河系内部的恒星群都更年轻，更富含金属。 凸出部最古老的恒星，如天琴座RR型恒星，出现在银河系星星形成和聚集的最早期。 这些观测将与补充光学勘测相结合，为研究隆起的结构、动力学和金属丰度奠定基础。该提案将提供约5，000颗RR型天琴座恒星的径向速度和[Fe/H]金属丰度，并提供RR型天琴座恒星朝向内星系的完整轨道分析。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

The investigator will observe a special class of old stars, called RR Lyrae stars, located toward the center of the Galaxy. Studying these stars provides a glimpse to how the Milky Way changed with time. The investigator will observe a large sample of these stars in order to reconstruct their motion through space. The reconstructed motions will then allow the investigator to distinguish which RR Lyrae stars are part of the halo, the disk, or the “Spheroidal Bulge” surrounding the center of the Milky Way. These measurements will lead to a better understand the early stages of the Milky Way formation. The investigator will recruit qualified students, targeting first generation and other underrepresented students within the science, technology, engineering and math (STEM) disciplines. These student researchers will collect data from telescopes, analyze the data, and present at conferences. The investigator will continue to lead the popular public science café series, organize star parties and work with the local Boys and Girls club to engage the local community.The investigator will use RR Lyrae stars as test probes to study the formation of the inner Galaxy. Using such ancient and metal-poor stars is important, as most of the stellar populations that have been used to understand the inner Galaxy have been younger and more metal-rich. The oldest stars in the Bulge, like the RR Lyrae stars, were present in the earliest episodes of star formation and assembly of our Galaxy. These observations will be combined with complementary optical surveys to provide the foundation of studies on the structure, dynamics and metallicity of the bulge. This proposal will provide both radial velocities and [Fe/H] metallicities for approximately 5,000 RR Lyrae stars and provide a full orbital analysis of the RR Lyrae stars toward the inner galaxy.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.