Old Star Clusters: Stellar Activity and Galactic Structure

老星团：恒星活动和星系结构摘要：一个长期项目将继续监测年龄与太阳相当的星团（20至80亿年）中主序疏散星团恒星的活动。这项工作的部分动机是为了更好地了解太阳的活动（过去、现在和未来）：太阳目前的活动水平是它这个年龄的恒星的典型水平吗？活动量会随着年龄的增长而下降吗？老恒星的衰落速度是否与太阳磁场活动的发电机理论相一致？在这里，使用洛厄尔天文台的珀金斯重新成像系统，对四个星团（年龄从20亿年到80亿年）中主序恒星的光球表面活动进行为期7年的光度监测将继续进行3年。其结果将是建立一个涵盖与太阳周期相当的持续时间的类太阳恒星的精确光度测量数据库，该数据库可能用于帮助回答这些问题。一项有大量本科生参与的配套研究也将进行，使用洛厄尔的相同设备，对银河系外盘很少研究的疏散星团进行表征。这项工作将用于为未来的项目提供目标。波士顿大学的所有本科生都可以参加。

AST-0507655Kenneth JanesBoston UniversityOld Star Clusters: Stellar Activity and Galactic StructureABSTRACTA long-term program to monitor the activity among main-sequence open-cluster stars in clusters of ages comparable to the Sun (2 to 8 billion years) will be continued. The work is motivated in part towards a better understanding solar activity (past, present, and future): is the current level of activity in the Sun typical of stars of its age? Does activity decline with age? Is the rate of decline in older stars consistent with the dynamo theory for magnetic activity in the Sun? Here the seven year photometric monitoring of photospheric surface activity among main-sequence stars in four cluster (of ages from 2 to 8 billion years) will be continued for another three years using the Perkins Re-Imaging System at the Lowell Observatory. The result will be a database of precision photometry of sun-like stars covering a duration comparable to the solar cycle which may be used to help answer such questions.A companion study with heavy undergraduate involvement will also be undertaken to characterize little studied open clusters in the outer disk of the Galaxy using the same equipment at Lowell. This work will be used to provide targets for future projects. Participation will be open to any undergraduate at Boston University.