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arXiv · astro-ph/0306168

A Re-evaluation of the Super Li-rich Star in NGC 6633

C. Laws·G. Gonzalez
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Abstract

We present a new abundance analysis of the super Li-rich star J37 and a comparison star in NGC 6633. We confirm the result of Deliyannis et al. that J37 has a Li abundance well above the meteoritic value, and we also confirm that Al, S, Si, Ca, Fe and Ni are super-solar, and C is sub-solar. We additionally find that Na, Sc, Ti are super-solar, while O is sub-solar. The abundance pattern of metals in J37 is generally consistent with the bulk composition of the Earth. We propose that accretion of circumstellar matter is the best explanation for these abundance anomalies, although we cannot rule out a secondary contribution from diffusion.

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C. Laws, G. Gonzalez. 2003-06-09. A Re-evaluation of the Super Li-rich Star in NGC 6633. https://doi.org/10.1086/377449

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