PI: Ryan M. Maderak, Indiana University, firstname.lastname@example.org
Address: Astronomy Department, Swain West 319, 727 E 3rd St., Bloomington, IN 47405-7105, USA
CoI: Constantine P. Deliyannis, Indiana University
CoI: Andrew Szentgyorgyi, CfA
Title: Oxygen Abundances at the Extremes of the Open Cluster Metallicity Range: NGC 2506
Abstract: The Galactic [O/Fe] versus [Fe/H] and [O/H] versus age relationships are of great importance for our understanding of Galactic chemical evolution. Although important questions persist at the most metal-poor end of field star studies ([Fe/H] < -2), two intriguing issues have emerged from studies of \textitopen clusters: (1) in sharp contrast to field star data, open clusters show \textitno convincing correlation of O to Fe, and (2) open clusters show a strong O-age relation. Whereas field stars do not generally allow exploration of the age parameter, open clusters can uniquely provide accurate knowledge of both [Fe/H] and age. It is possible that previous open cluster samples contained too small a range in Fe, or too few data, to reveal a robust trend of O to Fe. We therefore propose to test the reality of this perplexing result by further extending our WIYN/Hydra and MMT/Hectochelle program to critically low metallicity, namely NGC 2506, using MMT/Hectochelle. This cluster will provide the anchor for a robust determination of the O- Fe relationship, ultimately telling us whether Fe or age is the more important parameter.
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