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Related papers: The AMBRE Project: Constraining the lithium evolut…

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The study of the Milky Way stellar discs in the context of galaxy formation is discussed. In particular we explore the properties of the Milky Way disc using a new sample of about 550 dwarf stars for which we have recently obtained…

Astrophysics · Physics 2009-11-13 S. Feltzing , T. Bensby

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

Lithium abundances have been determined in more than 100 metal-poor halo stars both in the field and in clusters. From these data we find trends of Li with both temperature and metallicity and a real dispersion in Li abundances in the Spite…

Astrophysics · Physics 2009-11-11 Ann Merchant Boesgaard , Megan C. Novicki , Alex Stephens

Chemical abundances are an essential tool in untangling the Milky Way's enrichment history. However, the evolution of the interstellar medium abundance gradient with cosmic time is lost as a result of radial mixing processes. For the first…

We test a scenario in which radial migration could affect the Li abundance pattern of dwarf stars in the solar neighbourhood. This may confirm that the Li abundance in these stars can not serve as a probe for the Li abundance in the…

Aims. We present a spectroscopic analysis of a sample of evolved stars in M67 (turn-off, subgiant and giant stars) in order to bring observational constraints to evolutionary models taking into account non-standard transport processes.…

Solar and Stellar Astrophysics · Physics 2015-03-17 B. L. Canto Martins , A. Lèbre , A. Palacios , P. de Laverny , O. Richard , C. H. F. Melo , J. D. do Nascimento , J. R. De Medeiros

We investigate the chemical evolution of the Milky Way disc exploring various schemes of recent (last several Gyr) star formation episodes, as reported in recent observational works. We use a semi-analytical model with parametrized radial…

Astrophysics of Galaxies · Physics 2025-02-12 Tianxiang Chen , Nikos Prantzos

(Abridged) We contribute to our understanding of the evolution of young intermediate-mass stars by providing a comprehensive analysis of their lithium (Li) content. A sample of 71 intermediate-mass T Tauri (IMTT) and Herbig stars within the…

Lithium has confused scientists for decades at almost each scale of the universe. Lithium-rich giants are peculiar stars with lithium abundances over model prediction. A large fraction of lithium-rich low-mass evolved stars are…

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…

The emergence of the disc in our Galaxy and the relation of the thick and thin disc formation and evolution is still a matter of debate. The chemo-dynamical characterization of disc stars is key to resolve this question, in particular at…

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

In this paper, we study the formation and chemical evolution of the Milky Way disc with particular focus on the abundance patterns ([$\alpha$/Fe] vs. [Fe/H]) at different Galactocentric distances, the present-time abundance gradients along…

Astrophysics of Galaxies · Physics 2018-09-12 V. Grisoni , E. Spitoni , F. Matteucci

Observational data have revealed a clear dichotomy in the [{\alpha}/Fe] vs. [Fe/H] diagram of the Milky Way thick and thin disc stars. Many recent studies have shown evidences of a co-evolution phase between the high- and low-{\alpha} disc…

Astrophysics of Galaxies · Physics 2026-05-12 V. Grisoni , E. Spitoni , F. Matteucci

We have undertaken the study of the elemental abundances and kinematic properties of a metal-poor sample of candidate thick-disk stars selected from the RAVE spectroscopic survey of bright stars to differentiate among the present scenarios…

Context. About 0.2-2% of giant stars are Li-rich, whose lithium abundance (A(Li)) is higher than 1.5 dex. Among them, near 6% are super Li-rich with A(Li) exceeding 3.2 dex. Meanwhile, the formation mechanism of these Li-rich and super…

Solar and Stellar Astrophysics · Physics 2022-12-14 Jun Gao , Chunhua Zhu , Jinlong Yu , Helei Liu , Xizhen Lu , Jianrong Shi , Guoliang Lü

We develop a chemical evolution model in order to study the star formation history of the Milky Way. Our model assumes that the Milky Way is formed from a closed box-like system in the inner regions, while the outer parts of the disc…

Astrophysics of Galaxies · Physics 2015-06-10 O. Snaith , M. Haywood , P. Di Matteo , M. D. Lehnert , F. Combes , D. Katz , A. Gómez

Lithium and zirconium abundances (the latter taken as representative for s-process enrichment) are determined for a large sample of massive Galactic O-rich AGB stars, for which high resolution optical spectroscopy has been obtained…

Astrophysics · Physics 2009-11-11 D. A. Garcia-Hernandez , P. Garcia-Lario , B. Plez , A. Manchado , F. D'Antona , J. Lub , H. Habing

Thick disks are common in spiral and S0 galaxies and seem to be an inherent part of galaxy formation and evolution. Our own Milky Way is host to an old thick disk. The stars associated with this disk are enhanced in the alpha-elements as…

Astrophysics · Physics 2007-05-23 S. Feltzing

A highly homogeneous study of 23 halo field dwarf stars has achieved a Li abundance accuracy of 0.033 dex per star. The work shows that the intrinsic spread of the Li abundances of these stars at a given metallicity is <0.02 dex, and…

Astrophysics · Physics 2007-05-23 Sean G. Ryan
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