Abstract
NGC 1868 is a rich, blue globular-like cluster in the LMC, located sufficiently far from the main body of the Cloud to allow accurate faint photometry of its stars. Its C-M diagram shows a well-populated main sequence with a turnoff at M/sub v/approx. ==+0.4. The well-populated giant branch is much too blue to fit models with solar metals abundance. It has its faint red giant at B-V=+0.70, M/sub v/=+1.0, and a blue loop at M/sub v/=0.0 extending to B-V=+0.50. The brightest red giants reach M/sub v/approx.-0.5 and B-V=1.15. The best fit of the giant branch is with a Z of 0.001, a turnoff mass of 2.0 M/sub sun/, and an age of 7 x 10/sup 8/ years. Ten anomalously bright giants are found near the center of the cluster, and several hypotheses are suggested to explain them.
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