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Related papers: Origin of lithium enrichment in K giants

200 papers

A non-LTE analysis of K I resonance lines at 7664.91 and 7698.97 A was carried out for 15 red giants belonging to three globular clusters of different metallicity (M 4, M 13, and M 15) along with two reference early-K giants (rho Boo and…

Solar and Stellar Astrophysics · Physics 2015-05-13 Y. Takeda , H. Kaneko , N. Matsumoto , S. Oshino , H. Ito , T. Shibuya

The light element lithium is formed by nucleosynthesis during the Big Bang. Its abundance can help to define the parameters of the early universe. To find this primordial value, it is necessary to determine Li abundances in the oldest stars…

Solar and Stellar Astrophysics · Physics 2023-07-28 Ann Merchant Boesgaard , Constantine P. Deliyannis

Context. Galactic red novae are thought to be produced in stellar mergers between non-compact stars, such as main-sequence stars and cool giants. They are hoped to help in explaining physical processes involved in common envelope evolution…

Solar and Stellar Astrophysics · Physics 2023-04-26 Tomek Kamiński , Mirek Schmidt , Marcin Hajduk , Aleksandra Kiljan , Inna Izviekova , Adam Frankowski

Metal-poor stars are crucially important for understanding the early Galaxy, first stars, and the Universe. In this series of papers, we present a homogeneous non-local thermodynamic equilibrium (NLTE) abundances analysis of 12 elements for…

We consider WIYN/Hydra spectra of 329 photometric candidate members of the 420-Myr-old open cluster M48, and report Lithium detections or upper limits for 234 members and likely members. The 171 single members define a number of notable…

Solar and Stellar Astrophysics · Physics 2023-07-26 Qinghui Sun , Constantine P. Deliyannis , Aaron Steinhauer , Barbara J. Anthony-Twarog , Bruce A. Twarog

This paper presents the chemical abundance analysis of 217 stars in the metal-poor globular cluster NGC 6752, distributed from the turn-off to the lower red giant branch. Aluminium and Lithium abundances were derived through spectral…

Solar and Stellar Astrophysics · Physics 2022-02-09 J. Schiappacasse-Ulloa , S. Lucatello , M. J. Rain , A. Pietrinferni

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…

Solar and Stellar Astrophysics · Physics 2022-10-26 Sarah L. Martell , Matthew D. Shetrone

After a short historical (and highly subjective) introduction to the field, I discuss our current understanding of the origin and evolution of the light nuclides D, He-3, He-4, Li-6, Li-7, Be-9, B-10 and B-11. Despite considerable…

Astrophysics · Physics 2009-11-13 Nikos Prantzos

We present FLAMES/GIRAFFE spectroscopy obtained at the Very Large Telescope (VLT). Using these observations we have been able for the first time to observe the Li I doublet in the Main Sequence stars of a Globular Cluster. We also observed…

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

Despite the large number of studies focused on the characterisation of Li-rich stars and understanding the mechanisms leading to such enrichment, their origin remains a mystery. Magnetic activity, particularly the phenomena usually…

Solar and Stellar Astrophysics · Physics 2024-08-13 Inês Rolo , Elisa Delgado Mena , Maria Tsantaki , João Gomes da Silva

Capella is a spectroscopic binary consisting of two G-type giants, where the primary (G8III) is a normal red-clump giant while the secondary (G0III) is a chromospherically-active fast rotator showing considerable overabundance of Li as…

Solar and Stellar Astrophysics · Physics 2018-08-08 Yoichi Takeda , Osamu Hashimoto , Satoshi Honda

We adopt up-to-date 7Li yields from asymptotic giant branch stars in order to study the temporal evolution of 7Li in the solar neighbourhood in the context of a revised version of the two-infall model for the chemical evolution of our…

Astrophysics · Physics 2016-08-30 Donatella Romano , Francesca Matteucci , Paolo Ventura , Francesca D'Antona

Lithium abundances are presented for 91 dwarf and subgiant stars in the Galactic bulge. The analysis is based on line synthesis of the 7Li line at 6707 {\AA} in high-resolution spectra obtained during gravitational microlensing events, when…

Astrophysics of Galaxies · Physics 2020-02-26 T. Bensby , S. Feltzing , J. C. Yee , J. A. Johnson , A. Gould , M. Asplund , J. Meléndez , S. Lucatello

PDS365 is a newly detected rapidly rotating (vsin i = 20 km/s) single low mass giant star which with HD233517 and HD219025 forms a remarkable ensemble of single K giants with the unique properties of rapid rotation, very strong Li lines, an…

Astrophysics · Physics 2009-11-07 Natalia A. Drake , Ramiro de la Reza , Licio da Silva , David L. Lambert

After few minutes the Universe evolved through conditions of temperature and density which permitted the first synthesis of astrophysically interesting abundances of D, 3He, 4He and 7Li. The relic abundances are sensitive probes of the…

Astrophysics · Physics 2007-08-30 Paolo Molaro

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

This study investigates the temporal and spatial variations in lithium abundance within the Milky Way using a sample of 22,034 main-sequence turn-off (MSTO) stars and subgiants, characterised by precise stellar ages, 3D NLTE (non-local…

Astrophysics of Galaxies · Physics 2024-11-21 Tiancheng Sun , Shaolan Bi , Xunzhou Chen , Yuxi , Lu , Yuqin Chen , Ming-Yi Ding , Jianrong Shi , Hongliang Yan , Zhishuai Ge

Lithium is extensively known to be a good tracer of non-standard mixing processes occurring in stellar interiors. We present the results of a new large Lithium survey in red giant stars and combine it with surveys from the literature to…

Solar and Stellar Astrophysics · Physics 2020-01-08 C. Charbonnel , N. Lagarde , G. Jasniewicz , P. North , M. Shetrone , J. Krugler Hollek , V. V. Smith , R. Smiljanic , A. Palacios , G. Ottoni

Current observations indicate that stars with higher rotation rates appear to maintain more surface lithium, and the majority of lithium-rich giants are indeed red clump stars. Hence, we investigate the mechanisms behind lithium enrichment…

Solar and Stellar Astrophysics · Physics 2025-02-21 Xue-Feng Li , Jian-Rong Shi , Yan Li , Hong-Liang Yan , Jing-Hua Zhang

This contribution presents an overview of the evolution of Li abundances in stars of the Galactic thin and thick discs, from the observational point of view. The focus is on Li abundances obtained by recent projects and surveys. To separate…

Solar and Stellar Astrophysics · Physics 2020-06-23 Rodolfo Smiljanic