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Based on observations collected at the European Southern Observatory, La Silla, Chile; Kitt Peak National Observatory, Cerro Tololo Interamerican Observatory, and the Australia Telescope National Facility

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Visiting astronomer at Kitt Peak National Observatory

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Visiting astronomer at Cerro Tololo Interamerican Observatory

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Visiting astronomer at the European Southern Observatory, La Silla, Chile

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Currently on leave at the Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA

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Presently at: Pennsylvania State University, Department of Astronomy, 525 Davey Lab, University Park, PA 16803

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