PI: Barbara Anthony-Twarog, University of Kansas, firstname.lastname@example.org
Address: Dept. of Phys. & Astronomy, 1251 Wescoe Hall Dr., Lawrence, KS 66045-7550
CoI: Bruce A. Twarog, University of Kansas
Title: Extended Stromgren Photometry in the Intermediate-age Open Cluster, NGC 5822
Abstract: Open clusters remain invaluable objects for probing evolution on a galactic scale and testing the finer details of stellar evolution. In recent years we have focused on the study of open clusters as markers of Galactic disk evolution, evaluating the cluster parameters to test the reality and significance of detailed structure within the disk abundance gradient, confirming the apparent change in the slope of the gradient beyond the solar circle, evidence for an apparent inside-out development of the disk (Twarog et al. 1997). The current proposal is built around a comprehensive photometric study of the Hyades-age open cluster NGC 5822 as a prelude to high-dispersion spectroscopic analysis of the Li abundance for stars from the rich giant branch to the main sequence well below the so-called Li-dip. Our proposed CCD study on the extended Stromgren system, the first CCD study of this cluster on any photometric system, will supply reddening, metallicity, distance, and cluster age, while allowing us to identify and eliminate probable non- members and binaries, thereby optimizing the sample for spectroscopic followup.
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