Collaborative Research: Deep Astrometric and Radial Velocity Studies of Old Open Clusters

合作研究：旧疏散星团的深度天体测量和径向速度研究

• 批准号: 0406689
• 负责人: Imants Platais
• 金额: --
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-08-15 至 2008-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0406689&HistoricalAwards=false
• 关键词: Collaborative; Research; Deep; Astrometric; Radial

AST 0406689PI PlataisOpen clusters are collections of stars with similar ages and compositions, and as such provide a vital observational foundation for much of stellar astrophysics and stellar dynamics. The key for entry into these astrophysical laboratories is knowledge of the cluster membership, for stars in front of or behind a cluster appear to be within it. Since all stars gravitationally bound to a cluster move with very similar speed and direction, the path to identifying the members of a cluster is to measure the velocities for all stars visible within the cluster boundaries through proper motion and radial velocity determinations. This project is carrying out an exceptionally comprehensive and reliable census of the stellar and binary star populations in five rich old open clusters. The interface between stellar evolution and stellar dynamics is being explored through complete descriptions of the cluster mass functions, binary frequencies, and binary orbital elements as a function of radius, permitting detailed comparisons with n-body numerical simulations that include both dynamical and stellar evolution. The complex interplay between radiative and hydrodynamical processes within stellar cores is being explored through detailing the morphologies of main-sequence turnoff points. Broader Impacts: This project is enhancing the research and teaching skills of future scientists by integrating graduate student dissertations, undergraduate theses, and research experiences for other undergraduate students. This work is associated with the NSF Center for the Integration of Research, Teaching, and Learning at the University of Wisconsin. A trilateral Taiwan-Baltic collaboration assists in the training and education of students in recently disadvantaged countries.

AST 0406689 PI PlataisOpen星团是由年龄和成分相似的恒星组成的集合，因此为许多恒星天体物理学和恒星动力学提供了重要的观测基础。进入这些天体物理实验室的关键是要知道星团的成员，因为在星团前面或后面的恒星似乎都在星团内。由于所有受引力约束的恒星都以非常相似的速度和方向运动，因此识别星团成员的途径是通过自行和径向速度测定来测量星团边界内所有可见恒星的速度。该项目正在对五个丰富的老疏散星团中的恒星和双星星星种群进行特别全面和可靠的普查。恒星演化和恒星动力学之间的接口正在探索通过完整的描述的集群质量函数，二进制频率，和二进制轨道要素作为半径的函数，允许详细的比较与n体数值模拟，包括动力学和恒星演化。通过详细描述主序星转折点的形态，正在探索恒星核心内辐射和流体动力学过程之间的复杂相互作用。更广泛的影响：本项目通过整合研究生论文、本科生论文和其他本科生的研究经验，提高未来科学家的研究和教学技能。这项工作与威斯康星州大学的NSF研究、教学和学习一体化中心有关。台湾-波罗的海三边合作协助最近处于不利地位的国家的学生的培训和教育。