Membership, Rotation, Activity, and Lithium Abundances in a Selection of Nearby Clusters

这个项目将通过获取邻近星团中恒星的成员信息来扩展我们对像太阳这样的恒星如何演化的知识。长期以来，对星团的观测为恒星结构和演化理论提供了最好的联系。给定质量、成分和年龄的恒星模型可以预测光度和有效温度（颜色）。在一个星团中所有恒星年龄和化学成分相同的合理假设下，星团颜色与星等图提供了可以比较恒星模型的光度和有效温度的模板。利克天文台收集了1970年左右用36英寸折射镜拍摄的疏散星团的第一批时代玻璃板底片。在过去的三年里，对附近11个星团的第二个时代板块进行了拍摄。这些星团和另外4个星团的第二次时代摄影正在完成。然后使用合适的平板测量来确定星团中恒星的适当运动，从而估计单个恒星的隶属概率。将对几个星团中的成员恒星进行光谱观测，以确定其丰度、恒星活动和旋转。这个数据库将被PI和其他人用来更好地理解恒星活动的演变，锂丰度，以及不同年龄和金属丰度的太阳型恒星的旋转。更广泛的影响。这项研究将产生一个对研究疏散星团的质量和光度函数以及动态演化具有重要意义的数据库，也将对想要观察高色散星团成员的光谱观测者有用。这个数据库将免费提供。这笔拨款支持与德国和空间望远镜科学研究所的天文学家合作。

AST 0307585Jones, Burton F.This project will expand our knowledge of how stars like the Sun evolve by obtaining membership information for stars in nearby star clusters. Observations of star clusters have long provided the best link to theories of stellar structure and evolution. Stellar models of a given mass, composition, and age predict luminosity and effective temperature (color). Under the reasonable assumption that all stars in a cluster are the same age and chemical composition, cluster color versus magnitude diagrams provide templates against which the luminosity and effective temperature of stellar models can be compared. Lick Observatory has a collection of first epoch glass plate negatives of open star clusters taken around 1970 with the 36 inch refractor. Over the last three years second epoch plates of 11 nearby clusters were taken. The second epoch photography of these clusters, and 4 more clusters, is being completed. Suitable plate measurements are then used to determine proper motions for stars in the clusters and thence membership probability estimates for individual stars. Spectroscopic observations will be obtained of member stars in several of the clusters for the determination of abundances, stellar activity, and rotation. This database will be used by the PI and others toward a better understanding of the evolution of stellar activity, lithium abundance, and rotation in solar type stars different ages and metallicities. Broader Impacts. This research will produce a database with importance for studies of the mass and luminosity functions and the dynamical evolution of open star clusters, and will also be of use to spectroscopic observers who want to observe cluster members at high dispersion. This database will be made freely available. This grant supports collaboration with astronomers in Germany and at the Space Telescope Science Institute.