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Related papers: The evolution of Lithium: implications of a univer…

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Very high-quality spectra of 24 metal-poor halo dwarfs and subgiants have been acquired with ESO's VLT/UVES for the purpose of determining Li isotopic abundances. The derived 1D, non-LTE 7Li abundances from the LiI 670.8nm line reveal a…

We present VLT-UVES Li abundances for 28 halo dwarf stars between [Fe/H]=-2.5 and -3.5, 10 of which have [Fe/H]<-3. Four different T_eff scales have been used. Direct Infrared Flux Method (IRFM) has been used on the basis of 2MASS infrared…

Li abundances in the bulk of low-mass metal-poor stars are well reproduced by stellar evolution models adopting a constant initial abundance. However, a small number of stars have exceptionally high Li abundances, for which no convincing…

Solar and Stellar Astrophysics · Physics 2018-01-31 Haining Li , Wako Aoki , Tadafumi Matsuno , Yerra Bharat Kumar , Jianrong Shi , Takuma Suda , Gang Zhao

The depletion of lithium during the pre-main sequence and main sequence phases of stellar evolution plays a crucial role in the comparison of the predictions of big bang nucleosynthesis with the abundances observed in halo stars. In the…

Astrophysics · Physics 2011-05-05 M. H. Pinsonneault , T. P. Walker , G. Steigman , V. K. Narayanan

The $^6$Li abundance observed in metal poor halo stars exhibits a plateau similar to that for $^7$Li suggesting a primordial origin. However, the observed abundance of $^6$Li is a factor of $10^3$ larger and that of $^7$Li is a factor of 3…

The lithium problem arises from the significant discrepancy between the primordial 7Li abundance as predicted by BBN theory and the WMAP baryon density, and the pre-Galactic lithium abundance inferred from observations of metal-poor…

Astrophysics · Physics 2009-10-16 Richard H. Cyburt , Brian D. Fields , Keith A. Olive

We present Li abundances for 73 stars in the metallicity range -3.5 < [Fe/H] < -1.0 using improved IRFM temperatures (Casagrande et al. 2010) with precise E(B-V) values obtained mostly from interstellar NaI D lines, and high-quality…

Solar and Stellar Astrophysics · Physics 2015-05-14 J. Melendez , L. Casagrande , I. Ramirez , M. Asplund , W. J. Schuster

[ABRIDGED] We determine Li abundances for a well-studied sample of 714 F and G dwarf, turn-off, and subgiant stars in the solar neighbourhood. The analysis is based on line synthesis of the Li line at 6707 {\AA} in high-resolution and high…

Astrophysics of Galaxies · Physics 2018-08-01 Thomas Bensby , Karin Lind

Data from Gaia DR2 and APOGEE surveys revealed a relatively new component in the inner Galactic halo, which is likely the dynamical remnant of a disrupted dwarf galaxy named Gaia-Enceladus that collided with the Milky Way about 10 Gyrs ago.…

Astrophysics of Galaxies · Physics 2020-06-24 Paolo Molaro , Gabriele Cescutti , Xiaoting Fu

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

Of all the light elements, the evolution of lithium (Li) in the Milky Way is perhaps the most difficult to explain. Li is difficult to synthesize and is easily destroyed, making most stellar sites unsuitable for producing Li in sufficient…

Solar and Stellar Astrophysics · Physics 2022-07-20 Alex J. Kemp , Amanda I. Karakas , Andrew R. Casey , Benoit Cote , Robert G. Izzard , Zara Osborn

The lithium abundance in 62 halo dwarfs is determined from accurate equivalent widths reported in the literature and an improved infrared flux method (IRFM) temperature scale. The Li abundance of 41 plateau stars (those with Teff > 6000 K)…

Astrophysics · Physics 2009-11-10 Jorge Melendez , Ivan Ramirez

We adopt up-to-date 7Li yields from asymptotic giant branch stars in order to study the temporal evolution of this element in the solar neighbourhood. Several lithium stellar sources are considered besides the AGBs: Type II supernovae,…

Astrophysics · Physics 2016-11-03 Donatella Romano , Francesca Matteucci , Paolo Ventura , Francesca D'Antona

Using the cosmological constants derived from WMAP, the standard big bang nucleosynthesis (SBBN) predicts the light elements primordial abundances for 4He, 3He, D, 6Li and 7Li. These predictions are in satisfactory agreement with the…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-13 M. Spite , F. Spite , P. Bonifacio

A few topics concerning the early chemical evolution of the Milky Way are critically discussed. In particular, it is argued that: 1) Observed abundance patterns of extremely metal poor stars (of Pop. II) do not constrain the mass range of…

Astrophysics · Physics 2007-05-23 Nikos Prantzos

The combination of data from the Gaia satellite and large ground-based spectroscopic surveys recently lead to a milestone understanding of our Galaxy's formation history, marked by the identification of stellar remnants of the accreted…

Astrophysics of Galaxies · Physics 2026-05-25 C. T. Nguyen , G. Cescutti , M. M. Bennedik , P. Molaro , L. Magrini , A. J. Korn

Big bang nucleosynthesis (BBN) and the cosmic baryon density from cosmic microwave background anisotropies together predict a primordial Li7 abundance a factor of 2--3 higher than that observed in galactic halo dwarf stars. A recent…

Astrophysics · Physics 2008-12-18 Brian D. Fields , Keith A. Olive , Elisabeth Vangioni-Flam

Thanks to the accurate determination of the baryon density of the universe by the recent cosmic microwave background experiments, updated predictions of the standard model of Big Bang nucleosynthesis now yield the initial abundance of the…

Astrophysics · Physics 2015-06-24 C. Charbonnel , F. Primas

The $^6$Li abundance observed in metal poor halo stars appears to exhibit a plateau as a function of metallicity similar to that for $^7$Li, suggesting a big bang origin. However, the inferred primordial abundance of $^6$Li is $\sim$1000…

This contribution presents an overview of the evolution of Li abundances in stars of the Galactic thin and thick discs, from the observational point of view. The focus is on Li abundances obtained by recent projects and surveys. To separate…

Solar and Stellar Astrophysics · Physics 2020-06-23 Rodolfo Smiljanic