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Related papers: Lithium Abundances in the alpha Per Cluster

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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

As part of a long term effort to understand pre-main sequence Li burning, we have obtained high resolution spectroscopic observations of 14 late type stars (G0--M1) in the young open cluster IC~4665. Most of the stars have \ha filled-in and…

Astrophysics · Physics 2016-08-30 E. L. Martin , D. Montes

aims: Our aim is to determine Li abundances in TO stars of the Globular Cluster 47 Tuc and test theories about Li variations among TO stars. method: We make use of high resolution (R~ 43000), high signal-to-noise ratio (S/N=50--70) spectra…

This paper presents the chemical abundance analysis of 217 stars in the metal-poor globular cluster NGC 6752, distributed from the turn-off to the lower red giant branch. Aluminium and Lithium abundances were derived through spectral…

Solar and Stellar Astrophysics · Physics 2022-02-09 J. Schiappacasse-Ulloa , S. Lucatello , M. J. Rain , A. Pietrinferni

The orders of magnitude variation in lithium abundances of evolved stars have long been a puzzle. Diluted signals, ambiguous evolutionary states and unknown masses have made it challenging to both map the expected lithium signals and…

Solar and Stellar Astrophysics · Physics 2023-07-26 Jamie Tayar , Joleen K. Carlberg , Claudia Aguilera-Gómez , Maryum Sayeed

Observational constraints on the primordial lithium abundance are important for the evaluation of the baryonic density of the universe. Its precise determination however suffers from uncertainties due to the possible depletion of this…

Astrophysics · Physics 2009-10-30 Sylvie Vauclair , Corinne Charbonnel

Context. As a fragile element, lithium is a sensitive probe of physical processes occurring in stellar interiors. Aims. We aim at investigating the relationship between lithium abundance and rotation rate in low-mass members of the newly…

Solar and Stellar Astrophysics · Physics 2020-04-01 J. Arancibia-Silva , J. Bouvier , A. Bayo , P. A. B. Galli , W. Brandner , H. Bouy , D. Barrado

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

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…

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

Lithium depletion and enrichment in the cosmos is not yet well understood. To help tighten constraints on stellar and Galactic evolution models, we present the largest high-resolution analysis of Li abundances A(Li) to date, with results…

We present a study of beryllium (Be) abundances in a large sample of field solar-type dwarfs and sub-giants spanning a large range of effective temperatures. The analysis shows that Be is severely depleted for F stars, as expected by the…

Astrophysics · Physics 2009-11-10 N. C. Santos , G. Israelian , S. Randich , R. J. Garcia Lopez , R. Rebolo

In an attempt to carry out a systematic study on the behavior of the photospheric abundances of Li, C, and O (along with Fe) for Hyades main-sequence stars in the T_eff range of ~5000-7000K, we conducted an extensive spectrum-synthesis…

Solar and Stellar Astrophysics · Physics 2015-06-12 Yoichi Takeda , Satoshi Honda , Takashi Ohnishi , Michiko Ohkubo , Ryuko Hirata , Kozo Sadakane

We have computed a grid of up-to-date stellar evolutionary models including atomic diffusion, in order to study the evolution with time of the surface Li abundance in low-mass metal-poor stars. We discuss in detail the dependence of the…

Astrophysics · Physics 2009-11-06 Maurizio Salaris , Achim Weiss

We present the results of a spectroscopic survey of X-ray selected, low-mass candidate members of the young open cluster NGC 2547. Using a combination of photometry, spectroscopic indices and radial velocities we refine our candidate list…

Astrophysics · Physics 2009-11-07 R. D Jeffries , J. M. Oliveira , D. Barrado y Navascues , J. R. Stauffer

We present Li, Na, Al and Fe abundances of 199 lower red giant branch stars members of the stellar system Omega Centauri, using high-resolution spectra acquired with FLAMES at the Very Large Telescope. The A(Li) distribution is peaked at…

Solar and Stellar Astrophysics · Physics 2018-10-31 A. Mucciarelli , M. Salaris , L. Monaco , P. Bonifacio , X. Fu , S. Villanova

Differences in chemical composition among main sequence stars within a given cluster are probably due to differences in their masses and other effects such as radiative diffusion, magnetic field, rotation, mixing mechanisms, mass loss,…

Solar and Stellar Astrophysics · Physics 2014-01-21 T. Kilicoglu , R. Monier , L. Fossati

The abundances of alkali elements (Li, Na, and K) were determined from the Li I 6708, Na I 5682/5688, and K I 7699 lines by taking into account the non-LTE effect for 24 sharp-lined A-type stars v sin i < 50 km/s, 7000 K < Teff <10000 K,…

Solar and Stellar Astrophysics · Physics 2015-06-03 Yoichi Takeda , Dong-Il Kang , Inwoo Han , Byeong-Cheol Lee , Kang-Min Kim , Satoshi Kawanomoto , Naoko Ohishi

We have refined the estimate of the primordial level of $^7$Li abundance to an accuracy better than 10%, based on high-precision Li abundances for metal-poor halo stars, and a recent model of post-BBN (Big Bang Nucleosynthesis) chemical…

Astrophysics · Physics 2009-10-31 Takeru Ken Suzuki , Yuzuru Yoshii , Timothy C. Beers

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
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