Related papers: The Galactic Lithium Evolution Revisited

In this review, I will discuss a few problems which point to the need for improved stellar evolution models of halo stars. Current stellar evolution models do not match the observed $^7$Li abundance patterns, suggesting that the input…

Lithium-rich giant stars are rare and their existence challenges our understanding of stellar structure and evolution. We profit from the high-quality sample gathered with HARPS and UVES, in order to search for Li-rich giants and to…

I present a review of chemical evolution models of the solar neighborhood. I give special attention to the necessary ingredients to reproduce the observed [Xi/Fe] ratios in nearby metal and super metal rich stars, and to the chemical…

The aims of this paper are: 1) to revisit the Tc content of a sample of oxygen-rich asymptotic giant branch (AGB) variables and 2) to increase the number of such stars for which the Li abundance has been measured to provide constraints on…

Weak G-band (WGB) stars are a rare class of cool luminous stars that present a strong depletion in carbon, but also lithium abundance anomalies that have been little explored in the literature since the first discovery of these peculiar…

We present a non-local thermodynamic equilibrium abundance analysis of the resonance doublet Li I at 6707.8 A for 55 Galactic F and G supergiants and bright giants. The derived lithium abundances log \epsilon(Li) may be considered in three…

Stars destroy lithium (Li) in their normal evolution. The convective envelopes of evolved red giants reach temperatures of millions of K, hot enough for the 7Li(p,alpha)4He reaction to burn Li efficiently. Only about 1% of first-ascent red…

We review the main sources of LiBeB production and show that a primary mechanism is at work in the early Galaxy involving both ejection and acceleration of He, C and O at moderate energy, which by nuclear interaction with H and He produce…

Abundances of alpha-elements such as Ca and Mg in disk and halo stars are usually derived from equivalent widths lines measured on high resolution spectra, and assuming Local Thermodynamic Equilibrium (LTE) . In this paper, we present…

The standard model of primordial nucleosynthesis by the Big Bang as selected by the WMAP-based estimate of the baryon density ($\Omega_bh^2$) predicts an abundance of $^7$Li that is a factor of three greater than the generally reported…

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…

We have analyzed high-dispersion spectra in the Li 6708 Angstrom region for 167 stars within the anticenter cluster, NGC 2204. From 105 probable members, abundance analysis of 45 evolved stars produces [Fe/H] = -0.40 +/- 0.12, [Si/Fe] =…

In this article, we speculate on the possible mechanisms for Li enhancement origin in RGB stars based on a large data set of around 340,299 stars collected from the GALAH survey combined with the Gaia astrometry. Data has 51,982 low mass…

This presentation focuses on a recently discovered super-Li rich turnoff star in the old, metal poor globular cluster NGC 6397 (Koch et al. 2011, ApJL, 738, L29). Its unusually high NLTE lithium abundance of A(7Li) = 4.21, the highest Li…

We investigate the evolution of the star formation rate in the early Galaxy using beryllium and oxygen abundances in metal poor stars. Specifically, we show that stars belonging to two previously identified kinematical classes (the…

The first generation of stars is quite unique. The absence of metals likely affects their formation, with current models suggesting a much more top-heavy initial mass fraction than what we observe today, and some of their other properties,…

We present a comparison of the lithium abundances of stars with and without planetary-mass companions. New lithium abundances are reported in 79 planet hosts and 38 stars from a comparison sample. When the Li abundances of planet host stars…

High resolution UVES spectra of 40 main-sequence stars with -3.3 < [Fe/H] < -1.0 are used to derive S, Fe and Zn abundances from lines in the 400 - 950 nm region. For one star we also present novel observations of the SI triplet at 1.046…

We report the discovery of 23 lithium-rich post-main-sequence stars, identified from moderate-resolution SDSS spectroscopy and confirmed with high-resolution spectra taken at the Hobby-Eberly Telescope. These new Li-rich stars cover a broad…

We report novel observational evidence on the evolutionary status of lithium-rich giant stars by combining asteroseismic and lithium abundance data. Comparing observations and models of the asteroseismic gravity-mode period spacing…