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Related papers: Lithium-rich giants in the Galactic thick disk

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The stellar evolution of lithium-rich (Li-rich) giant stars at very low metallicities remains largely unexplored to date. Using two recent large LAMOST catalogues of field, low-mass giant stars (both Li-rich and Li-poor) with metallicities…

Astrophysics of Galaxies · Physics 2025-12-30 Ramiro de la Reza , Felix Llorente de Andrés , Emilio J. Alfaro , Carolina Chavero

Standard stellar evolution model predicts a severe depletion of lithium (Li) abundance during the first dredge-up process (FDU). Yet a small fraction of giant stars are still found to preserve a considerable amount of Li in their…

Lithium is a fragile but crucial chemical element in the universe, exhibits interesting and complex behaviors. Thanks to the massive spectroscopic data from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)…

Lithium-rich giant stars are rare and their existence challenges our understanding of stellar structure and evolution. We profit from the high-quality sample gathered with HARPS and UVES, in order to search for Li-rich giants and to…

Solar and Stellar Astrophysics · Physics 2023-06-21 M. Tsantaki , E. Delgado-Mena , D. Bossini , S. G. Sousa , E. Pancino , J. H. C. Martins

Standard stellar evolution model predicts a severe depletion of lithium (Li) abundance during the first dredge up process (FDU). Yet a small fraction of giant stars are still found to preserve a considerable amount of Li in their…

Solar and Stellar Astrophysics · Physics 2020-01-08 Qi Gao , Jian-Rong Shi , Hong-Liang Yan , Tai-Sheng Yan , Mao-Sheng Xiang , Yu-Tao Zhou , Chun-Qian Li , Gang Zhao

We report the discovery of eight lithium-rich field giants found in a high resolution spectroscopic sample of over 700 metal-poor stars ([Fe/H]<-0.5) selected from the RAVE survey. The majority of the Li-rich giants in our sample are very…

In this study, we explore the evolution of lithium in giant stars based on data assembled from the literature on asteroseismology and Li abundances for giants. Our final sample of 187 giants consists of 44 red giant branch (RGB), 140 core…

Solar and Stellar Astrophysics · Physics 2021-05-07 Deepak , David L. Lambert

Li-rich giants serve as valuable tracers of stellar evolution and surface enrichment processes, for which a statistically large and homogeneous sample is crucial. Using the massive low-resolution ($R \sim 1800$) spectroscopic dataset from…

Stellar models predict that lithium (Li) inside a star is destroyed during the first dredge-up phase, yet 1.2% of red giant stars are Li-rich. We aim to uncover possible origins of this population, by analysing 1155 Li-rich giants (A(Li)…

About one percent of giants\upcite{Brown1989} are detected to have anomalously high lithium (Li) abundances in their atmospheres, conflicting directly with the prediction of the standard stellar evolution models\upcite{Iben1967}, and making…

Lithium is one of the few elements produced during the Big Bang Nucleosynthesis in the early universe. Moreover, its fragility makes it useful as a proxy for stellar environmental conditions. As such, the lithium abundance in old systems is…

A search for lithium is performed on seven metal poor dwarfs with metallicities ranging from [Fe/H]=-1.5 down to [Fe/H]=-3.0 but showing disk-like kinematics. These stars belong to the metal poor tail of the Galactic thick disk and they may…

Astrophysics · Physics 2016-01-13 P. Molaro , P. Bonifacio , L. Pasquini

We present a non-local thermodynamic equilibrium abundance analysis of the resonance doublet Li I at 6707.8 A for 55 Galactic F and G supergiants and bright giants. The derived lithium abundances log \epsilon(Li) may be considered in three…

The discovery of lithium-rich giants contradicts expectations from canonical stellar evolution. Here we report on the serendipitous discovery of 20 Li-rich giants observed during the Gaia-ESO Survey, which includes the first nine Li-rich…

We report novel observational evidence on the evolutionary status of lithium-rich giant stars by combining asteroseismic and lithium abundance data. Comparing observations and models of the asteroseismic gravity-mode period spacing…

Solar and Stellar Astrophysics · Physics 2021-05-26 Raghubar Singh , Bacham E. Reddy , Simon W. Campbell , Yerra Bharat Kumar , Mathieu Vrard

[ABRIDGED] We determine Li abundances for a well-studied sample of 714 F and G dwarf, turn-off, and subgiant stars in the solar neighbourhood. The analysis is based on line synthesis of the Li line at 6707 {\AA} in high-resolution and high…

Astrophysics of Galaxies · Physics 2018-08-01 Thomas Bensby , Karin Lind

A small fraction of red giants are known to be lithium (Li) rich, in contradiction with expectations from stellar evolutionary theory. A possible explanation for these atypical giants is the engulfment of a Li-rich planet or brown dwarf by…

Solar and Stellar Astrophysics · Physics 2016-10-05 Claudia Aguilera-Gómez , Julio Chanamé , Marc Pinsonneault , Joleen Carlberg

The chemical evolution of lithium in the Milky Way represents a major problem in modern astrophysics. Indeed, lithium is, on the one hand, easily destroyed in stellar interiors, and, on the other hand, produced at some specific stellar…

Astrophysics of Galaxies · Physics 2016-10-26 G. Guiglion , P. de Laverny , A. Recio-Blanco , C. C. Worley , M. De Pascale , T. Masseron , N. Prantzos , S. Mikolaitis

Using the sample of 348 stars from the PennState-Torun Centre for Astronomy Planet Search, for which uniformly determined atmospheric parameters are available, with chemical abundances and rotational velocities presented here, we…

Solar and Stellar Astrophysics · Physics 2015-06-22 M. Adamow , A. Niedzielski , E. Villaver , A. Wolszczan , G. Nowak

The lithium abundances in a few percent of giants exceed the value predicted by the standard stellar evolution models, and the mechanisms of Li enhancement are still under debate. The Large Sky Area Multi-Object Fiber Spectroscopic…

Solar and Stellar Astrophysics · Physics 2018-07-18 Y. T. Zhou , J. R. Shi , H. L. Yan , Q. Gao , J. B. Zhang , G. Zhao , K. Pan , Y. B. Kumar
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