PI: Barbara Anthony-Twarog, University of Kansas, firstname.lastname@example.org
Address: Physics Department, 1251 Wescoe Hall Dr., 1082 Malott Hall, Lawrence, KS 66045, USA
CoI: Bruce Twarog, Univ. of Kansas
CoI: Constantine Deliyannis, Indiana University
Title: Extended Stromgren Photometry in NGC 2506 and NGC 2204
Abstract: Open clusters remain invaluable targets for probing evolution on a galactic scale, as well as testing the finer details of stellar structure and evolution. Through the application of precision photometry on the extended Stromgren system, we have derived the critical parameters of reddening, metallicity, age, and membership for key clusters, supplying insight into the detailed structure of the Galactic abundance gradient (Twarog et al. 1997), lending support to an inside-out development of the disk. These same cluster parameters are also crucial input in our current attempt to characterize the evolution of Li as a function of stellar mass, age, and metallicity from the main sequence through the giant branch using open clusters of intermediate- age. The temporal evolution of this fragile element not only probes sub- photospheric structure in a unique way, it supplies a critical constraint to our understanding of Cosmology. The open clusters of interest are NGC 2204 and NGC 2506, neither of which have been studied with intermediate-band photometry.
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