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Related papers: A Comparative Study on Lithium Abundances in Solar…

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Lithium is predicted, and observed, to be depleted in contracting, low-mass pre main sequence (PMS) stars. Yet these stars reach the zero age main sequence (ZAMS) with a spread in lithium abundance at a given effective temperature that is…

Solar and Stellar Astrophysics · Physics 2025-04-28 R. J. Jackson , R. D. Jeffries , E. Tognelli

We examine the internal structure of solar-like stars in detail between 0.8 and 1.4M Sun and during pre-main sequence phase. Recent opacity computations of OPAL along with a new hydrodynamical mixing process have been considered. We also…

Astrophysics · Physics 2008-11-26 L. Piau , S. Turck-Chieze

Rotational velocity, lithium abundance, and the mass depth of the outer convective zone are key parameters in the study of the processes at work in the stellar interior, in particular when examining the poorly understood processes operating…

Solar and Stellar Astrophysics · Physics 2015-05-19 J. D. do Nascimento , J. S. da Costa , J. R. De Medeiros

Two problems are discussed here. The first one is the 0.4 dex discrepancy between the 7Li abundance derived from the spectra of metal-poor halo stars on the one hand, and from Big Bang nucleosynthesis, based on the cosmological parameters…

Mapping lithium evolution for evolved stars will provide restrictions and constraints on the fundamental stellar interior physical processes, which further shed light on our understanding of the theory of stellar structure and evolution.…

Solar and Stellar Astrophysics · Physics 2021-09-29 Jinghua Zhang , Jian-Rong Shi , Hong-Liang Yan , Yaguang Li , Qi Gao , Chun-Qian Li , Xianfei Zhang , Shuai Liu , Shaolan Bi , Gang Zhao , Yan Li

We analise the behavior of lithium abundance as a function of effective temperature, projected rotational velocity, orbital period and eccentricity for a sample of 68 binary systems with giant component and orbital period ranging from about…

Astrophysics · Physics 2009-11-07 J. M. Costa , L. da Silva , J. D. do Nascimento , J. R. De Medeiros

Calcium abundance in the atmosphere of Am stars is examined as a function of their evolutionary state within the main sequence. New spectroscopic abundances as well as abundances abtained photometrically by Guthrie (1987) are used, since…

Astrophysics · Physics 2007-05-23 M. Kunzli , P. North

Helium abundances and atmospheric parameters have been determined from high resolution spectra for a new sample of 46 bright hot subdwarf B (sdB) stars. The helium abundances have been measured with high accuracy. We confirm the correlation…

Solar and Stellar Astrophysics · Physics 2011-12-14 S. Geier , U. Heber , H. Edelmann , L. Morales-Rueda , D. Kilkenny , D. O'Donoghue , T. R. Marsh , C. Copperwheat

Beryllium and oxygen abundances have been derived in a sample of F-type field stars for which lithium abundances had been measured previously, with the aim of obtaining observational constraints to discriminate between the different mixing…

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

We investigate a population of transiting planets that receive relatively modest stellar insolation, indicating equilibrium temperatures $< 1000$ K, and for which the heating mechanism that inflates hot Jupiters does not appear to be…

Earth and Planetary Astrophysics · Physics 2015-05-28 Neil Miller , Jonathan J. Fortney

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

We report the evidence that several low-mass stars (<~0.4 Msun) of the Orion and Upper Scorpius clusters have lithium abundances well below the interstellar value. Due to time-dependent depletion, our result implies stellar ages greater…

Astrophysics · Physics 2015-11-11 Francesco Palla , Sofia Randich

A large number of stellar evolution models with [Fe/H] = -2.3 and -3.3 have been calculated in order to determine the primordial $^7$Li abundance and to test current stellar evolution models by a comparison to the extensive database of Li…

Astrophysics · Physics 2009-10-22 Brian Chaboyer , P. Demarque

We aim to constrain the mixing processes in low-mass stars by investigating the behaviour of the Li surface abundance after the main sequence. We take advantage of the data from the sixth internal data release of Gaia-ESO, idr6, and from…

A search for lithium is performed on seven metal poor dwarfs with metallicities ranging from [Fe/H]=-1.5 down to [Fe/H]=-3.0 but showing disk-like kinematics. These stars belong to the metal poor tail of the Galactic thick disk and they may…

Astrophysics · Physics 2016-01-13 P. Molaro , P. Bonifacio , L. Pasquini

Abundance measurements of the light elements lithium, beryllium, and boron are playing an increasingly important role in the study of stellar physics. Because these elements are easily destroyed in stars at temperatures 2--4 million K, the…

Astrophysics · Physics 2009-10-30 Edward F. Brown

Results from detailed spectroscopic analyses of stars hosting massive planets are employed to search for trends between abundances and condensation temperatures. The elements C, S, Na, Mg, Al, Ca, Sc, Ti, V, Cr, Mn, Fe, Ni and Zn are…

Astrophysics · Physics 2009-11-13 Guillermo Gonzalez

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 have determined Be abundances in 50 F and G dwarfs in the mass range of 0.9 $\leq$ M$_\odot$ $\leq$ 1.1 as determined by Lambert & Reddy. The effective temperatures are 5600 to 6400 K and metallicities from $-$0.65 to +0.11. The spectra…

Astrophysics · Physics 2015-05-13 Ann Merchant Boesgaard , Julie A. Krugler
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