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Related papers: Lithium Depletion in Pre-Mainsequence Solar-Like S…

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Precise Li abundances are determined for 54 giant stars mostly evolving across the Hertzsprung gap. We combine these data with rotational velocity and with information related to the deepening of the convective zone of the stars to analyse…

Astrophysics · Physics 2009-11-10 P. de Laverny , J. D. Jr do Nascimento , A. Lebre , J. R. De Medeiros

We have used medium resolution spectra to search for evidence that proto-stellar objects accrete at high rates during their early 'assembly phase'. Models predict that depleted lithium and reduced luminosity in T-Tauri stars are key…

Astrophysics of Galaxies · Physics 2015-06-16 Darryl J. Sergison , N. J. Mayne , Tim Naylor , R. D. Jeffries , Cameron P. M. Bell

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

The surface content of lithium (Li) and beryllium (Be) in stars can reveal important information about the temperature structure and physical processes in their interior regions. This study focuses on solar-type stars with a sample that is…

Solar and Stellar Astrophysics · Physics 2022-12-14 Ann Merchant Boesgaard , Constantine P. Deliyannis , Michael G. Lum , Ashley Chontos

Lithium and beryllium are destroyed at different temperatures in stellar interiors. As such, their relative abundances offer excellent probes of the nature and extent of mixing processes within and below the convection zone. We determine Be…

Solar and Stellar Astrophysics · Physics 2015-06-24 M. Tucci Maia , J. Meléndez , M. Castro , M. Asplund , I. Ramírez , T. R. Monroe , J. D. do Nascimento , D. Yong

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 obtain lithium abundances for G and K stars in Blanco 1, an open cluster with an age similar to, or slightly younger than, the Pleiades. We critically examine previous spectroscopic abundance analyses of Blanco 1 and conclude that while…

Astrophysics · Physics 2009-10-30 R. D. Jeffries , D. J. James

We propose here that the lithium decrease at super-solar metallicities observed in high resolution spectroscopic surveys can be explained by the interplay of mixed populations, coming from the inner regions of the Milky Way disc. The lower…

Astrophysics of Galaxies · Physics 2019-03-13 G. Guiglion , C. Chiappini , D. Romano , F. Matteucci , F. Anders , M. Steinmetz , I. Minchev , P. de Laverny , A. Recio-Blanco

Lithium abundances, radial velocities and rotational velocities are reported for 20 candidate F, G and K stars of the sparse Coma Berenices open cluster. All the stars are proper-motion selected, and our radial velocities support the…

Astrophysics · Physics 2009-11-06 A. Ford , R. D. Jeffries , D. J. James , J. R. Barnes

Measurements of lithium abundances in solar-type stars have shown that standard models of stellar evolution are incapable of explaining the observed depletion as a function of stellar age. Beryllium is one of the lightest elements that can…

The disagreement between theoretical predictions and observations for surface lithium abundance in stars is a long-standing problem, which indicates that the adopted physical treatment is still lacking in some points. However, thanks to the…

Solar and Stellar Astrophysics · Physics 2015-06-11 E. Tognelli , S. Degl'Innocenti , P. G. Prada Moroni

We derive atmospheric parameters and lithium abundances for 671 stars and include our measurements in a literature compilation of 1381 dwarf and subgiant stars. First, a "lithium desert" in the effective temperature (Teff) versus lithium…

Solar and Stellar Astrophysics · Physics 2015-06-05 I. Ramirez , J. R. Fish , D. L. Lambert , C. Allende Prieto

We determine lithium (Li) abundances for solar twins in the M67 open cluster to add valuable information about the correlation between Li depletion and stellar age and, then, better understand stellar structure and evolution. We use high…

Solar and Stellar Astrophysics · Physics 2020-01-08 Marilia Carlos , Jorge Melendez , Jose-Dias do Nascimento , Matthieu Castro

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

We compare the properties of recent samples of the lithium abundances in halo stars to one another and to the predictions of theoretical models including rotational mixing, and we examine the data for trends with metal abundance. We find…

Astrophysics · Physics 2008-11-26 M. H. Pinsonneault , G. Steigman , T. P. Walker , V. K. Narayanan

Lithium abundances are presented for a sample of 181 nearby F and G dwarfs with accurate {\it Hipparcos} parallaxes. The stars are on circular orbits about the Galactic centre and, hence, are identified as belonging to the thin disk. This…

Astrophysics · Physics 2009-11-10 David L. Lambert , Bacham E. Reddy

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…

The primordial Lithium Problem is intimately connected to the assumption that ${}^{7}{\rm Li}$ observed in metal-poor halo stars retains its primordial abundance, which lies significantly below the predictions of standard big-bang…

Astrophysics of Galaxies · Physics 2022-04-08 Brian D. Fields , Keith A. Olive

Evolutionary models taking into account radiative accelerations, thermal diffusion, and gravitational settling for 28 elements, including all those contributing to OPAL stellar opacities, have been calculated for solar metallicity stars of…

Astrophysics · Physics 2009-11-10 G. Michaud , O. Richard , J. Richer , Don A. VandenBerg

We report the discovery of a lithium dip (Li-dip) in the stellar "Snake" (age = $35 \pm 5$ Myr), challenging the classical view that Li-dips emerge only at ages $\gtrsim 150$ Myr. Using high-resolution spectra from GALAH DR4 ($R \sim…

Solar and Stellar Astrophysics · Physics 2026-02-10 Yun-Yi Zhang , Hai-Jun Tian , Jian-Rong Shi , Cheng-Cheng Xie , Xiang-Ming Yang
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