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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…

Determinations of beryllium abundance in stars, together with lithium, provide a key tool to investigate the so far poorly understood extra-mixing processes at work in stellar interiors. We measured Be in three open clusters,complementing…

Astrophysics · Physics 2009-11-13 S. Randich , F. Primas , L. Pasquini , P. Sestito , R. Pallavicini

We have derived beryllium abundances in a wide sample of stars hosting planets, with spectral types in the range F7V-K0V, aimed at studying in detail the effects of the presence of planets on the structure and evolution of the associated…

Evolution of the 7Li abundance in the convection zone of the Sun during different stages of its life time is considered to explain its low photospheric value in comparison with that of the solar system meteorites. Lithium is intensively and…

Solar and Stellar Astrophysics · Physics 2017-02-01 F. Thevenin , A. V. Oreshina , V. A. Baturin , A. B. Gorshkov , P. Morel , J. Provost

The simultaneous investigation of Li and Be in stars is a powerful tool in the study of the evolutionary mixing processes. Here, we present beryllium abundances in stars along the whole evolutionary sequence of the open cluster IC 4651.…

Solar and Stellar Astrophysics · Physics 2015-05-14 Rodolfo Smiljanic , L. Pasquini , C. Charbonnel , N. Lagarde

(abridged) Recent analyses have reported low lithium but high beryllium abundances on the solar surface; however, standard solar models (SSMs) predict Li abundances that are ~30$\sigma$ away from the observed value. In this study, we aim to…

Solar and Stellar Astrophysics · Physics 2025-10-29 Masanobu Kunitomo , Gaël Buldgen , Tristan Guillot

Lithium is an excellent tracer of mixing in stars as it is destroyed (by nuclear reactions) at a temperature around $\sim 2.5\times 10^6$ K. The lithium destruction zone is typically located in the radiative region of a star. If the…

Astrophysics · Physics 2007-05-23 Brian Chaboyer

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 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

The abundance of beryllium in the oldest, most metal-poor stars acts as a probe of early star formation and Galactic chemical evolution. We have analyzed high-resolution, high signal-to-noise Keck/HIRES spectra of 24 stars with [Fe/H] from…

Astrophysics of Galaxies · Physics 2011-02-11 Jeffrey A. Rich , Ann Merchant Boesgaard

We present high-resolution spectroscopic observations of the \ion{Li}{1} resonance line in a sample of 62 stars that belong to 31 common-proper motion pairs with twin F or G-type components. Photospheric abundances of lithium were derived…

Astrophysics · Physics 2009-11-07 Eduardo L. Martin , Gibor Basri , Yakiv Pavlenko , Yuri Lyubchik

The surface abundance of lithium on the Sun is 140 times less than protosolar, yet the temperature at the base of the surface convective zone is not hot enough to burn Li. A large range of Li abundances in solar type stars of the same age,…

We study lithium depletion in low-mass and solar-like stars as a function of time, using a new diffusion coefficient describing extra-mixing taking place at the bottom of a convective envelope. This new form is motivated by…

Solar and Stellar Astrophysics · Physics 2017-08-16 I. Baraffe , J. Pratt , T. Goffrey , T. Constantino , D. Folini , M. V. Popov , R. Walder , M. Viallet

An extensive beryllium abundance analysis was conducted for 118 solar analogs (along with 87 FGK standard stars) by applying the spectrum synthesis technique to the near-UV region comprising the Be II line at 3131.066 A, in an attempt to…

Solar and Stellar Astrophysics · Physics 2015-05-27 Yoichi Takeda , Akito Tajitsu , Satoshi Honda , Satoshi Kawanomoto , Hiroyasu Ando , Takashi Sakurai

[abridged] Beryllium is a pure product of cosmic ray spallation. This implies a relatively simple evolution in time of the beryllium abundance and suggests its use as a time-like observable. We study the evolution of Be in the early Galaxy…

Astrophysics of Galaxies · Physics 2015-05-13 R. Smiljanic , L. Pasquini , P. Bonifacio , D. Galli , R. G. Gratton , S. Randich , B. Wolff

Globular clusters host multiple stellar populations that display star-to-star variation of light elements that are affected by hot hydrogen burning (e.g., He, C, N, O). Several scenarios have been suggested to explain these variations. Most…

Solar and Stellar Astrophysics · Physics 2022-03-30 Riano E. Giribaldi , Rodolfo Smiljanic

We have investigated the abundance anomalies of lithium for stars with planets in the temperature range of 5600--5900 K reported by Israelian and coworkers, as compared to 20 normal stars at the same temperature and metallicity ranges. Our…

Astrophysics · Physics 2010-11-11 Y. Q. Chen , G. Zhao

We have obtained the first beryllium measurements of late F/early G-type stars in the old open cluster M67 (4.5 Gyr) and in the intermediate age cluster IC 4651 (1.7 Gyr). One member of the young cluster IC 2391 (~50 Myr) was also observed.…

Astrophysics · Physics 2009-11-07 Sofia Randich , Francesca Primas , Luca Pasquini , Roberto Pallavicini

Abundances of beryllium in metal-poor stars scale linearly with metallicity down to [Fe/H] ~ -3.0. In the stars where Be has been detected at this extremely metal-poor regime, an increased abundance scatter has been previously reported.…

Solar and Stellar Astrophysics · Physics 2021-02-10 Rodolfo Smiljanic , Mateusz G. Zych , Luca Pasquini

Beryllium is not destroyed as easily as Li, so the abundances of Li and Be together can tell us more about the internal physical processes in stars than either element can alone. We have obtained high-resolution (45,000) and high…

Astrophysics · Physics 2009-11-07 Ann Merchant Boesgaard , Jeremy R. King