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Related papers: Lithium and binarity in M67

200 papers

We determine the age and mass of the three best solar twin candidates in open cluster M67 through lithium evolutionary models. We computed a grid of evolutionary models with non-standard mixing at metallicity [Fe/H] = 0.01 with the…

Solar and Stellar Astrophysics · Physics 2015-05-20 M. Castro , J. D. do Nascimento , K. Biazzo , J. Melendez , J. R. De Medeiros

We report on the determination of the lithium abundance [A(Li)] of 52 solar-like stars. For 41 objects the A(Li) here presented corresponds to the first measurement. We have measured the equivalent widths of the 6708\AA\ lithium feature in…

Solar and Stellar Astrophysics · Physics 2015-07-07 R. López-Valdivia , J. B. Hernández-Águila , E. Bertone , M. Chávez , F. Cruz-Saenz de Miera , E. M. Amazo-Gómez

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…

Double lined spectroscopic binaries in an evolved stage of evolution are expected to be extremely rare since they must consist of equally luminous and thus almost equally evolved objects, which requires an extremely similar initial mass. In…

Astrophysics · Physics 2016-01-27 Maarten Reyniers , Hans Van Winckel

We present lithium abundances for 119 main-sequence stars in the old open cluster NGC 188 (age = 6.3 Gyr), using high-resolution, high signal-to-noise ratio spectra from WIYN/Hydra. We observe the stars over multiple nights and measure…

Solar and Stellar Astrophysics · Physics 2025-09-19 Qinghui Sun , Constantine P. Deliyannis , Bruce A. Twarog , Barbara J. Anthony-Twarog

Convergent lines of evidence suggest that globular clusters host multiple stellar populations. It appears that they experience at least two episodes of star formation whereby a fraction of first-generation stars contribute astrated ejecta…

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

High-resolution CTIO 4-m/HYDRA spectroscopy of the super-metal-rich open cluster NGC 6253 ([Fe/H]=+0.43+/-0.01) has been used to study the stellar lithium (Li) abundances near the cluster's turnoff. NGC 6253 greatly expands the range of…

Solar and Stellar Astrophysics · Physics 2015-06-11 Jeffrey D. Cummings , Constantine P. Deliyannis , Barbara Anthony-Twarog , Bruce Twarog , Ryan M. Maderak

Lithium (Li) abundance is an age indicator for G, K, and M stellar types, as its abundance decreases over time for these spectral types. However, despite the observational efforts made over the past few decades, the role of rotation,…

Solar and Stellar Astrophysics · Physics 2024-05-15 D. Cuenda-Muñoz , D. Barrado , M. A. Agüeros , J. L. Curtis , H. Bouy

The behavior of lithium (Li) in Population I main sequence stars challenges standard stellar theory. Two phenomena stand out: the solar Li problem which extends to Li depletion in solar analogs and the Li dip observed in mid-F stars within…

Solar and Stellar Astrophysics · Physics 2025-08-28 Xuefeng Li , Jianrong Shi , Yan Li , Hongliang Yan , Jinghua Zhang

A spectroscopic investigation of the lithium resonance doublet in $\xi$ Boo A and $\xi$ Boo B in terms of both abundance and isotopic ratio is presented. We obtained new $R$=130\,000 spectra with a signal-to-noise ratio (S/N) per pixel of…

Solar and Stellar Astrophysics · Physics 2023-01-04 Klaus G. Strassmeier , Matthias Steffen

Determination of the lithium depletion boundary (LDB), i.e., the observational limit below which the cores of very low-mass objects do not reach high enough temperature for Li destruction, has been used to obtain ages for several open…

Solar and Stellar Astrophysics · Physics 2018-04-04 Eduardo L. Martín , Nicolas Lodieu , Yakiv Pavlenko , Víctor J. S. Béjar

Stellar clusters are open windows to understand stellar evolution. Specifically, the change with time and the dependence on mass of different stellar properties. As such, they are our laboratories where different theories can be tested. We…

Solar and Stellar Astrophysics · Physics 2016-12-14 D. Barrado , H. Bouy , J. Bouvier , E. Moraux , L. M. Sarro , E. Bertin , J. C. Cuillandre , J. R. Stauffer , J. Lillo-Box , A. Pollock

The evolution of lithium abundance over a star's lifetime is indicative of transport processes operating in the stellar interior. We revisit the relationship between lithium content and rotation rate previously reported for cool dwarfs in…

Solar and Stellar Astrophysics · Physics 2018-06-13 J. Bouvier , D. Barrado , E. Moraux , J. Stauffer , L. Rebull , L. Hillenbrand , A. Bayo , I. Boisse , H. Bouy , E. DiFolco , J. Lillo-Box , M. Morales Calderon

It has recently been suggested that all giant stars with mass below 2 $M_{\odot}$ suffer an episode of surface lithium enrichment between the tip of the red giant branch (RGB) and the red clump (RC). We test if the above result can be…

Lithium is one of the few elements produced during the Big Bang Nucleosynthesis in the early universe. Moreover, its fragility makes it useful as a proxy for stellar environmental conditions. As such, the lithium abundance in old systems is…

Li abundances are derived for a sample of bulgelike stars with isochronal ages of 10-11 Gyr. These stars have orbits with pericentric distances, Rp, as small as 2-3 kpc and Zmax < 1 kpc. The sample comprises G and K dwarf stars in the…

Astrophysics · Physics 2009-11-07 Luciana Pompeia , Beatriz Barbuy , Michel Grenon , Bruno Castilho

We utilize spectroscopically derived model atmosphere parameters and the \ion{Li}{1} $\lambda6104$ subordinate line and the $\lambda6708$ doublet to derive lithium abundances for 12 members of the Upper-Centaurus Lupus (UCL) and…

Solar and Stellar Astrophysics · Physics 2015-06-03 Eric J. Bubar , Marc Schaeuble , Jeremy R. King , Eric E. Mamajek , John R. Stauffer

We discuss the high lithium abundances in the secondary stars of X-ray binaries. We show that no lithium production in these stars is necessary, and that the abundances can be explained simply due to the tidally locked rotation of the…

Astrophysics · Physics 2009-11-10 T. J. Maccarone , P. G. Jonker , A. I. Sills

We aim to determine abundances of Li, O and Na in a sample of of 110 turn-off (TO) stars, in order to study the evolution of light elements in this cluster and to put our results in perspective with observations of other globular and open…

Solar and Stellar Astrophysics · Physics 2014-05-28 V. Dobrovolskas , A. Kučinskas , P. Bonifacio , S. A. Korotin , L. Sbordone , E. Caffau , D. Prakapavičius , M. Steffen , H. -G. Ludwig , F. Royer