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

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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

In this paper we adopt a chemical evolution model, which is an improved version of the Chiappini, Matteucci and Gratton (1997) model, assuming two main accretion episodes for the formation of the Galaxy. The present model takes into account…

Astrophysics · Physics 2009-11-06 Cristina Chiappini , Francesca Matteucci , Donatella Romano

The lithium present in the photospheres of solar-type stars is transported to the inner parts by convection, reaching regions even somewhat below the convection zone, by non-standard transport mechanisms. In stars with deeper convective…

Solar and Stellar Astrophysics · Physics 2023-05-04 Giulia Martos , Jorge Meléndez , Anne Rathsam , Gabriela Carvalho Silva

The "stellar" solution to the cosmological lithium problem proposes that surface depletion of lithium in low-mass, metal-poor stars can reconcile the lower abundances found for Galactic halo stars with the primordial prediction. Globular…

Solar and Stellar Astrophysics · Physics 2015-05-18 K. Lind , F. Primas , C. Charbonnel , F. Grundahl , M. Asplund

We calculate the ages, orbits and phase-space coordinates for a sample of $\sim$4 million LAMOST and Gaia stars. The ages are crossmatched and compared with values from two other popular age catalogs which derive the ages using different…

Astrophysics of Galaxies · Physics 2021-12-08 John J. Vickers , Juntai Shen , Zhao-Yu Li

In recent years much interest has been shown in the process of thermohaline mixing in red giants. In low and intermediate mass stars this mechanism first activates at the position of the bump in the luminosity function, and has been…

Solar and Stellar Astrophysics · Physics 2015-06-23 John Lattanzio , Lionel Siess , Ross Church , George Angelou , Richard Stancliffe , Carolyn Doherty , Thomas Stephen , Simon Campbell

Stellar migration is an important dynamical process in Galactic disk. Here we model the radial stellar migration in the Galactic disk with an analytical method, then add it to detailed Galactic chemical evolution model to study the…

Astrophysics of Galaxies · Physics 2015-06-15 Yue Wang , Gang Zhao

Lithium is a fundamental element for studying the mixing mechanisms acting in the stellar interiors, for understanding the chemical evolution of the Galaxy and the Big Bang nucleosynthesis. The study of Li in stars of open clusters…

Solar and Stellar Astrophysics · Physics 2015-06-15 P. Francois , L. Pasquini , K. Biazzo , P. Bonifacio , R. Palsa

As stars traverse the Milky Way, their orbits evolve through perturbations that alter their orbital radii. These changes arise from two mechanisms: churning, which modifies angular momentum, and blurring, which induces eccentric orbits…

Astrophysics of Galaxies · Physics 2025-12-18 M. L. L. Dantas , R. Smiljanic , R. S. de Souza , P. B. Tissera , L. Magrini

The formation and evolution of the Milky Way's disc, bar, and bulge remain fundamentally limited by the lack of a contiguous, Galaxy-wide, high-precision chemo-dynamical map. Key open questions - including the survival or destruction of the…

Trends in the enrichment of elements with stellar ages are a powerful avenue to identify unexplained origins of the elements. We investigate the stellar abundance trends of low to intermediate-mass stars using the GALAH DR3 high-resolution…

Astrophysics of Galaxies · Physics 2024-10-15 Evans K. Owusu , Sven Buder , Ashley J. Ruiter , Ivo R. Seitenzahl , Nicolás Rodríguez-Segovia

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

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

Metallicities of both gas and stars decline toward large radii in spiral galaxies, a trend known as the radial metallicity gradient. We quantify the evolution of the metallicity gradient in the Milky Way as traced by APOGEE red giants with…

The observed amount of lithium for low metallicity population II stars (known as the Spite plateau) is a factor of $\sim 3-5$ lower than the predictions of the standard cosmology. Since the observations are limited to the local Universe…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-06 Maxim Pospelov , Niayesh Afshordi

We find that hot jupiter host stars within the T$_\mathrm{eff}$ range 5900-6300K show lower Li abundances, by 0.14 dex, than stars without detected planets. This offset has a significance at the level 7$\sigma$, pointing to a stronger…

We investigate the effect of new stellar models, which take rotation into account, computed for very low metallicities on the chemical evolution of the earliest phases of the Milky Way. We check the impact of these new stellar yields on a…

Astrophysics · Physics 2008-11-26 C. Chiappini , R. Hirschi , F. Matteucci , G. Meynet , S. Ekstrom , A. Maeder

The Milky Way serves as a template for understanding the formation and evolution of late-type massive disk galaxies since we can obtain detailed chemical and kinematic information for large samples of individual stars. However, the early…

LTE abundances of light elements in extremely metal-poor (EMP) stars have been previously derived from high quality spectra. New derivations, free from the NLTE effects, will better constrain the models of the Galactic chemical evolution…

Astrophysics of Galaxies · Physics 2015-05-14 S. M. Andrievsky , Monique Spite , S. A. Korotin , F. Spite , P. Bonifacio , R. Cayrel , P. François , V. Hill

Aims. This study aims to determine the level and constancy of the Spite plateau as definitively as possible from homogeneous high-quality VLT-UVES spectra of 19 of the most metal-poor dwarf stars known. Methods. Our high-resolution (R ~…