中文
相关论文

相关论文: Lithium-Rich Field Giants in the Sloan Digital Sky…

200 篇论文

We report the discovery of 23 lithium-rich post-main-sequence stars, identified from moderate-resolution SDSS spectroscopy and confirmed with high-resolution spectra taken at the Hobby-Eberly Telescope. These new Li-rich stars cover a broad…

太阳与恒星天体物理 · 物理学 2022-10-26 Sarah L. Martell , Matthew D. Shetrone

Context: Lithium is a fragile element, which is easily destroyed in the stellar interior. The existence of lithium-rich giants still represents a challenge for stellar evolution models. Aims: We have collected a large database of…

太阳与恒星天体物理 · 物理学 2015-05-27 L. Monaco , S. Villanova , C. Moni Bidin , G. Carraro , D. Geisler , P. Bonifacio , O. A. Gonzalez , M. Zoccali , L. Jilkova

In this article, we speculate on the possible mechanisms for Li enhancement origin in RGB stars based on a large data set of around 340,299 stars collected from the GALAH survey combined with the Gaia astrometry. Data has 51,982 low mass…

太阳与恒星天体物理 · 物理学 2019-01-29 Deepak , Bacham Eswar Reddy

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…

太阳与恒星天体物理 · 物理学 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

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-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…

太阳与恒星天体物理 · 物理学 2023-06-21 M. Tsantaki , E. Delgado-Mena , D. Bossini , S. G. Sousa , E. Pancino , J. H. C. Martins

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)…

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)…

The presence of a large amount of Li in giants is still a mystery. Most of the super Li-rich giants reported in recent studies are in the solar metallicity regime. Here, we study the five metal-poor super Li-rich giants (SLRs) from GALAH…

太阳与恒星天体物理 · 物理学 2024-03-26 Antony Susmitha , Anohita Mallick , Bacham E. Reddy

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…

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…

太阳与恒星天体物理 · 物理学 2015-06-22 M. Adamow , A. Niedzielski , E. Villaver , A. Wolszczan , G. Nowak

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…

We present Lithium abundance determination for a sample of K giant stars in the galactic bulge. The stars presented here are the only 13 stars with detectable Lithium line (6767.18 A) among ~400 stars for which we have spectra in this…

太阳与恒星天体物理 · 物理学 2015-05-13 O. A. Gonzalez , M. Zoccali , L. Monaco , V. Hill , S. Cassisi , D. Minniti , A. Renzini , B. Barbuy , S. Ortolani , A. Gomez

With an aim to shed light on the origin of Li anomaly observed in a small fraction of red giants, we carried out a spectroscopic study on the observational characteristics of selected 20 bright Li-rich giants, in comparison with a large…

太阳与恒星天体物理 · 物理学 2017-09-20 Yoichi Takeda , Akito Tajitsu

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…

太阳与恒星天体物理 · 物理学 2021-05-07 Deepak , David L. Lambert

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…

太阳与恒星天体物理 · 物理学 2021-05-26 Raghubar Singh , Bacham E. Reddy , Simon W. Campbell , Yerra Bharat Kumar , Mathieu Vrard

We present a critical analysis of the nature of the so-called Li-rich RGB stars. For a majority of the stars, we have used Hipparcos parallaxes to determine masses and evolutionary states by comparing their position on the…

天体物理学 · 物理学 2007-05-23 Corinne Charbonnel , Suchitra C. Balachandran

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…

星系天体物理 · 物理学 2025-12-30 Ramiro de la Reza , Felix Llorente de Andrés , Emilio J. Alfaro , Carolina Chavero

Lithium abundances for red giants in the GALAH DR3 survey are studied. The rare examples of Li-enriched stars with abundances A(Li) $\geq 1.5$ are confirmed to be He-core burning stars belonging to or evolved from the red clump with similar…

太阳与恒星天体物理 · 物理学 2021-08-25 Deepak , David L. Lambert
‹ 上一页 1 2 3 10 下一页 ›