Related papers: The evolution of Lithium: implications of a univer…
The uncertainties which still plague our understanding of the evolution of the light nuclides D, 3He and 4He in the Galaxy are described. Measurements of the local abundance of deuterium range over a factor of 3. The observed dispersion can…
Lithium abundances in a sample of halo dwarfs have been redetermined by using the new T$_{eff}$ derived by Fuhrmann et al (1994) from modelling of the Balmer lines. These T$_{eff}$ are reddening independent, homogeneous and of higher…
We explore possible depletion factors for Li6 in the three stars where it has been detected. To this end, we assume that 6Li/H scales as 16O/H throughout the galactic evolution, an assumption motivated by the observations of a similar…
The success of primordial nucleosynthesis has been limited by the long-standing Lithium problem. We use a self-consistent perturbative analysis of the effects of relevant theoretical parameters on primordial nucleosynthesis, including…
Standard stellar evolution model predicts a severe depletion of lithium (Li) abundance during the first dredge-up process (FDU). Yet a small fraction of giant stars are still found to preserve a considerable amount of Li in their…
In this contribution we discuss the use of the surface Li abundance in lower RGB stars as alternative diagnostic of the primordial Li abundance. These stars are located in the portion of the RGB after the completion of the First Dredge-Up…
The $^7$Li abundance calculated in BBN with the baryon-to-photon ratio fixed from fits to the CMB power spectrum is inconsistent with the observed lithium abundances on the surface of metal-poor halo stars. Previous cosmological solutions…
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…
A model scenario has recently been introduced to explain the presence of very strong Li lines in the spectra of some low mass K giant stars (de la Reza et al. 1996). In this scenario all ordinary, Li poor, K giants become Li rich during a…
In the standard hot big bang nucleosynthesis (BBN) model the primordial abundances of H, H2, He3, He4, and Li7, fix the baryon density of the universe, $\Omega_b$, via the baryon-to-photon ratio, $\eta$, for a given Hubble parameter. Recent…
We review the Galactic chemical evolution of Li6 and compare these results with recent observational determinations of the lithium isotopic ratio. In particular, we concentrate on so-called standard Galactic cosmic-ray nucleosynthesis in…
We derive atmospheric parameters and lithium abundances for 671 stars and include our measurements in a literature compilation of 1381 dwarf and subgiant stars. First, a "lithium desert" in the effective temperature (Teff) versus lithium…
The cosmological Li problem is the observed discrepancy between Li abundance, A(Li), measured in Galactic dwarf, old and metal-poor stars (traditionally assumed to be equal to the initial value A(Li)_0), and that predicted by standard Big…
Recent spectroscopic observations of metal poor stars have indicated that both $^7$Li and $^6$Li have abundance plateaus with respect to the metallicity. Abundances of $^7$Li are about a factor three lower than the primordial abundance…
High resolution (R=110000), very high S/N spectra, centered on the 6707.8A LiI line have been obtained with the ESO Coude Echelle Spectrometer for five, metal-poor (-0.8 < [Fe/H] < -0.6) disk stars in the turnoff region of the HR-diagram.…
To alleviate the discrepancy between the prediction of the primordial lithium abundance in the universe and the abundances observed in Pop II dwarfs and subgiant stars, it has been suggested that the stars observable today have undergone…
Recent new high-precision abundance data for Galactic halo stars suggest important primary nitrogen production in very metal-poor massive stars. Here, we compute a new model for the chemical evolution of the Milky Way aimed at explaining…
Context. Recently, for the first time the abundance of P has been measured in disk stars. This provides the opportunity of comparing the observed abundances with predictions from theoretical models. Aims. We aim at predicting the chemical…
The cosmological lithium problem, that is, the discrepancy between the lithium abundance predicted by the Big Bang nucleosynthesis and the one observed for the stars of the 'Spite plateau', is one of the long standing problems of modern…
This work aims to investigate the behaviour of the lithium abundance in stars with and without detected planets. Our study is based on a sample of 1332 FGK main-sequence stars with measured lithium abundances, for 257 of which planets were…