A Search for Lithium-rich Giants among Stars with Infrared Excesses
نویسندگان
چکیده
منابع مشابه
Lithium-rich Giants in Globular Clusters
Although red giants deplete lithium on their surfaces, some giants are Li-rich. Intermediate-mass asymptotic giant branch (AGB) stars can generate Li through the Cameron–Fowler conveyor, but the existence of Li-rich, low-mass red giant branch (RGB) stars is puzzling. Globular clusters are the best sites to examine this phenomenon because it is straightforward to determine membership in the clus...
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The application to main-sequence stars of the rotation-induced mixing theory in the presence of μ-gradients leads to partial mixing in the lithium destruction region, not visible in the atmosphere. The induced lithium depletion becomes visible in the sub-giant phase as soon as the convective zone deepens enough. This may explain why the observed “ lithium dilution ” is smoother and the final di...
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Aims. We report the detection of an unusually high lithium content in HD 232 862, a field giant classified as a G8II star, and hosting a magnetic field. Methods. With the spectropolarimeters ESPaDOnS at CFHT and NARVAL at TBL, we have collected high resolution and high signal-to-noise spectra of three giants : HD 232 862, KU Peg and HD 21 018. From spectral synthesis we have inferred stellar pa...
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ژورنال
عنوان ژورنال: The Astronomical Journal
سال: 1998
ISSN: 0004-6256
DOI: 10.1086/300614