Lithium in LMC Carbon Stars
نویسنده
چکیده
Nineteen carbon stars that show lithium enrichment in their atmospheres have been discovered among a sample of 674 carbon stars in the Large Magellanic Cloud. Six of the Li-rich carbon stars are of J-type, i.e., with strong C isotopic features. No superLi-rich carbon stars were found. The incidence of lithium enrichment among carbon stars in the LMC is much rarer than in the Galaxy, and about five times more frequent among J-type than among N-type carbon stars. The bolometric magnitudes of the Lirich carbon stars range between −3.3 and −5.7. Existing models of Li-enrichment via the hot bottom burning process fail to account for all of the observed properties of the Li-enriched stars studied here.
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تاریخ انتشار 2003