ON INFRARED EXCESSES ASSOCIATED WITH Li-RICH K GIANTS
نویسندگان
چکیده
منابع مشابه
Polarimetry of Li - rich giants ⋆
Context. Protoplanetary nebulae typically present non-spherical envelopes. The origin of such geometry is still controversial. There are indications that it may be carried over from an earlier phase of stellar evolution, such as the AGB phase. But how early in the star’s evolution does the non-spherical envelope appear? Aims. Li-rich giants show dusty circumstellar envelopes that can help answe...
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The analyses of high resolution infrared spectra have been done for CN lines in oxygen-rich cool evolved stars including 2 K giants, 20 M giants and 1 S-type star. Since CN lines analyzed in the present work are weak and resolved well, they are appropriate for quantitative analyses. CN lines of ∆v =−2 and −1 sequences (red system) which are in the Kand the H-window regions, respectively, give t...
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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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ژورنال
عنوان ژورنال: The Astronomical Journal
سال: 2015
ISSN: 1538-3881
DOI: 10.1088/0004-6256/150/4/123