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Related papers: A Test of Pre-Main-Sequence Lithium Depletion Mode…

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The main goal of this work is to evaluate the correlation between Li abundance, age, and mass. Using high-quality ESO/HARPS data (R $\simeq$ 115 000; 270 $\leq$ SNR $\leq$ 1000), we measured Li abundances via spectral synthesis of the…

Solar and Stellar Astrophysics · Physics 2023-09-15 Anne Rathsam , Jorge Meléndez , Gabriela Carvalho Silva

Stellar masses are a fundamental property to understand models of pre-main sequence evolution, but their values derived from Hertzsprung-Russell (HR) diagrams are strongly model dependent. We benchmark pre-main sequence stellar evolutionary…

The position of pre-main-sequence or protostars in the Hertzsprung--Russell diagram is often used to determine their mass and age by comparison with pre-main-sequence evolution tracks. On the assumption that the stellar models are accurate,…

Astrophysics · Physics 2009-10-31 Christopher A. Tout , Mario Livio , Ian A. Bonnell

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…

We investigated the possibility of producing helium enhanced stars in globular clusters by accreting polluted matter during the pre-main sequence phase. We followed the evolution of two different classes of pre-main sequence accreting…

Solar and Stellar Astrophysics · Physics 2015-11-04 E. Tognelli , P. G. Prada Moroni , S. Degl'Innocenti

We have performed a new and homogeneous analysis of all the Li data available in the literature for main sequence stars (spectral-types from late F to K) in open clusters. In the present paper we focus on a detailed investigation of MS Li…

Astrophysics · Physics 2009-11-11 P. Sestito , S. Randich

We present an analysis of the lithium abundances in late spectral type binaries of different ages. They belong to several open clusters (Pleiades, Hyades and M67), as well as to Chromospherically Active Binary Systems (CABS). All these…

Astrophysics · Physics 2007-05-23 David Barrado y Navascues

We explore the sensitivity in open cluster ages obtained by the lithium depletion boundary (LDB) technique to the stellar model input physics. The LDB age technique is limited to open clusters with ages ranging from 20 to 200 Myr. Effective…

Astrophysics · Physics 2009-11-10 Christopher J. Burke , Marc H. Pinsonneault , Alison Sills

We present the initial results of a study of the surface lithium abundance in a sample of low-mass members (M~0.4-1.0 Msun) of the Orion Nebula Cluster (ONC) that provide an independent clock to estimate stellar ages. We report discovery of…

Astrophysics · Physics 2009-11-11 F. Palla , S. Randich , E. Flaccomio , R. Pallavicini

We assess the impact of starspots on the evolution of late-type stars during the pre-main sequence (pre-MS) using a modified stellar evolution code. We find that heavily spotted models of mass 0.1-1.2\msun\ are inflated by up to $10$%…

Solar and Stellar Astrophysics · Physics 2015-07-15 Garrett Somers , Marc H. Pinsonneault

We performed a detailed analysis of the main theoretical uncertainties affecting the age at the lithium depletion boundary (LDB). To do that we computed almost 12000 pre-main sequence models with mass in the range [0.06, 0.4] M_sun by…

Solar and Stellar Astrophysics · Physics 2015-06-24 Emanuele Tognelli , Pier Giorgio Prada Moroni , Scilla Degl'Innocenti

Previous studies of open clusters have shown that lithium depletion is not only strongly age dependent but also shows a complex pattern with other parameters that is not yet understood. For pre- and main-sequence late-type stars, these…

Rotational mixing is a prime candidate for explaining the gradual depletion of lithium from the photospheres of cool stars during the main sequence. However, previous mixing calculations have relied primarily on treatments of angular…

Solar and Stellar Astrophysics · Physics 2016-09-28 Garrett Somers , Marc H. Pinsonneault

The prediction of the PLANCK-constrained primordial lithium abundance in the Universe is in discordance with the observed Li abundances in warm Population II dwarf and subgiant stars. Among the physically best motivated ideas, it has been…

Lithium abundances and rotation, determined for 120 subgiant stars in Lebre et al. (1999) are analyzed. To this purpose, the evolutionary status of the sample as well as the individual masses have been determined using the HIPPARCOS…

Astrophysics · Physics 2007-05-23 J. D. do Nascimento , C. Charbonnel , A. Lebre , P. de Laverny , J. R. De Medeiros

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 Lithium Depletion Boundary (LDB) is a robust method for accurately determining the ages of young clusters, but most pre-main-sequence models used to derive LDB ages do not include the effects of magnetic activity on stellar properties.…

Solar and Stellar Astrophysics · Physics 2015-06-22 Aaron J. Juarez , Phillip A. Cargile , David J. James , Keivan G. Stassun

The present work aims to examine in detail the depletion of lithium in solar twins to better constrain stellar evolution models and investigate its possible connection with exoplanets. We employ spectral synthesis in the region of the…

Solar and Stellar Astrophysics · Physics 2019-03-20 M. Carlos , J. Melendez , L. Spina , L. A. dos Santos , M. Bedell , I. Ramirez , M. Asplund , J. L. Bean , D. Yong , J. Yana Galarza , A. Alves-Brito

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

Aims: We study the influence of rotation and disc lifetime on lithium depletion of pre-main sequence (PMS) solar-type stars. Methods: The impact of rotational mixing and of the hydrostatic effects of rotation on lithium abundances are…

Solar and Stellar Astrophysics · Physics 2015-06-05 P. Eggenberger , L. Haemmerlé , G. Meynet , A. Maeder