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Related papers: Lithium-Rich Giants in Globular Clusters

200 papers

We present Li, Na, Al and Fe abundances of 199 lower red giant branch stars members of the stellar system Omega Centauri, using high-resolution spectra acquired with FLAMES at the Very Large Telescope. The A(Li) distribution is peaked at…

Solar and Stellar Astrophysics · Physics 2018-10-31 A. Mucciarelli , M. Salaris , L. Monaco , P. Bonifacio , X. Fu , S. Villanova

We have performed a search among low mass red giants for finding evidence for merger scenario for triggering He-flash and subsequent Li enhancement. We chose a sample of red giants from GALAH survey with well-measured Li abundances, and…

Solar and Stellar Astrophysics · Physics 2023-01-27 Anohita Mallick , Bacham E. Reddy , C. Muthumariappan

The surface lithium abundance A(Li) of warm metal-poor dwarf stars exhibits a narrow plateau down to [Fe/H]~-2.8 dex, while at lower metallicities the average value drops by 0.3 dex with a significant star-by-star scatter (called lithium…

Solar and Stellar Astrophysics · Physics 2022-06-01 A. Mucciarelli , L. Monaco , P. Bonifacio , M. Salaris , M. Deal , M. Spite , O. Richard , R. Lallement

The presence of multiple populations in globular clusters has been well established thanks to high-resolution spectroscopy. It is widely accepted that distinct populations are a consequence of different stellar generations: intra-cluster…

Solar and Stellar Astrophysics · Physics 2015-06-24 V. D'Orazi , R. G. Gratton , G. C. Angelou , A. Bragaglia , E. Carretta , J. C. Lattanzio , S. Lucatello , Y. Momany , A. Sollima , G. Beccari

Galactic Globular clusters (GCs) are now known to harbour multiple stellar populations, which are chemically distinct in many light element abundances. It is becoming increasingly clear that asymptotic giant branch (AGB) stars in GCs show…

Solar and Stellar Astrophysics · Physics 2016-04-27 B. T. MacLean , S. W. Campbell , G. M. De Silva , J. Lattanzio , V. DOrazi , J. D. Simpson , Y. Momany

Multiple stellar populations (MPs) are a distinct characteristic of Globular Clusters (GCs). Their general properties have been widely studied among main sequence, red giant branch (RGB) and horizontal branch (HB) stars, but a common…

Solar and Stellar Astrophysics · Physics 2021-03-31 E. P. Lagioia , A. P. Milone , A. F. Marino , M. Tailo , A. Renzini , M. Carlos , G. Cordoni , E. Dondoglio , S. Jang , A. Karakas , A. Dotter

We have gathered near-infrared $zyJ$-band high resolution spectra of nearly 300 field red giant stars with known lithium abundances in order to survey their \species{He}{i} $\lambda$10830 absorption strengths. This transition is an…

We report the discovery of two Li-rich giant stars (fainter than the red giant branch bump) in the stellar system Omega Centauri using GIRAFFE-FLAMES spectra. These two stars have A(Li)=1.65 and 2.40 dex and they belong to the main…

Solar and Stellar Astrophysics · Physics 2019-03-13 A. Mucciarelli , L. Monaco , P. Bonifacio , M. Salaris , X. Fu , S. Villanova

The aim of this work is to search for Li-rich giants in a sample of clusters where planets have been searched, thus we can study the planet engulfment scenario to explain Li replenishment using a proper comparison sample of stars without…

Solar and Stellar Astrophysics · Physics 2016-02-17 E. Delgado Mena , M. Tsantaki , S. G. Sousa , M. Kunitomo , V. Adibekyan , P. Zaworska , N. C. Santos , G. Israelian , C. Lovis

We have serendipitously discovered an extremely lithium-rich star on the red giant branch of the globular cluster M3 (NGC 5272). An echelle spectrum obtained with the Keck I HIRES reveals a Li I 6707 Angstrom resonance doublet of 520…

A model scenario has recently been introduced to explain the presence of very strong Li lines in the spectra of some low mass K giant stars (de la Reza et al. 1996). In this scenario all ordinary, Li poor, K giants become Li rich during a…

Astrophysics · Physics 2009-10-30 R. de la Reza , N. A. Drake , L. da Silva , C. A. O. Torres , E. L. Martin

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…

Solar and Stellar Astrophysics · Physics 2024-03-26 Antony Susmitha , Anohita Mallick , Bacham E. Reddy

We investigate the properties of 1262 red giant stars with high photospheric abundances of lithium observed by the GALAH and \Ktwo-HERMES surveys, and discuss them in the context of proposed mechanisms for lithium enrichment and…

The recent discovery of low-mass red giants with enhanced atmospherical Li abundance in galactic low-metallicity stellar clusters adds to the mysterious phenomenon of the Li-rich giants. We propose a combined scenario for the Li-enrichment:…

Astrophysics · Physics 2007-05-23 P. A. Denissenkov , A. Weiss

The aims of this paper are: 1) to revisit the Tc content of a sample of oxygen-rich asymptotic giant branch (AGB) variables and 2) to increase the number of such stars for which the Li abundance has been measured to provide constraints on…

Solar and Stellar Astrophysics · Physics 2015-05-14 Stefan Uttenthaler , Thomas Lebzelter

Weak G-band (WGB) stars are a rare class of cool luminous stars that present a strong depletion in carbon, but also lithium abundance anomalies that have been little explored in the literature since the first discovery of these peculiar…

Solar and Stellar Astrophysics · Physics 2015-06-03 A. Palacios , M. Parthasarathy , Y. Bharat Kumar , G. Jasniewicz

Almost several decades after the discovery of the first multiple populations in galactic globular clusters (GC) the debate on their formation is still extremely current and NGC2808 remains one of the best benchmark to test any scenario for…

Solar and Stellar Astrophysics · Physics 2018-07-18 Marcella Di Criscienzo , Paolo Ventura , Francesca D'Antona , Flavia Dell'Agli , Marco Tailo

Thanks to the high multiplex and efficiency of Giraffe at the VLT we have been able for the first time to observe the Li I doublet in the Main Sequence (MS) stars of a Globular Cluster. At the same time we observed Li in a sample of…

Astrophysics of Galaxies · Physics 2015-05-14 J. I. González Hernández , P. Bonifacio , E. Caffau , M. Steffen , H. -G. Ludwig , N. Behara , L. Sbordone , R. Cayrel , S. Zaggia

The majority of the inhomogeneities in the chemical composition of Globular Cluster (GC) stars appear due to primordial enrichment. The most studied model today claims that the ejecta of Asymptotic Giant Branch (AGB) stars of high mass…

Astrophysics · Physics 2007-05-23 Francesca D'Antona , Paolo Ventura , Vittoria Caloi

The existence of one percent of lithium-rich giant stars among normal, lithium-poor giant stars continues to be poorly explained. By merging two catalogues, one containing 10,535 lithium-rich giant stars with lithium abundances ranging from…

Solar and Stellar Astrophysics · Physics 2024-12-09 R. de la Reza