相关论文: The Galactic Lithium Evolution Revisited
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…
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…
High lithium-7 ($\mathrm{^7Li}$) abundances in giants are indicative of non-standard physical processes affecting the star. Mechanisms that could produce this signature include contamination from an external source, such as planets, or…
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…
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.…
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…
The primordial abundances of light elements produced in the standard theory of Big Bang nucleosynthesis (BBN) depend only on the cosmic ratio of baryons to photons, a quantity inferred from observations of the microwave background. The…
Lithium is extensively known to be a good tracer of non-standard mixing processes occurring in stellar interiors. We present the results of a new large Lithium survey in red giant stars and combine it with surveys from the literature to…
Nuclear interactions of ions accelerated at the surface of flaring stars can produce fresh isotopes in stellar atmospheres. Although this nucleosynthesis is not significant for the chemical evolution of the Galaxy, it can be important for a…
A search for lithium is performed on seven metal poor dwarfs with metallicities ranging from [Fe/H]=-1.5 down to [Fe/H]=-3.0 but showing disk-like kinematics. These stars belong to the metal poor tail of the Galactic thick disk and they may…
We revisit large spectroscopic data sets for field stars from the literature to derive the upper Li envelope in the high metallicity regime in our Galaxy. We take advantage of Gaia EDR3 data and state-of-the-art stellar models to precisely…
Context: The stellar production of the light element lithium is still a matter of debate. Aims: We report the detection of low-mass, Li-rich Asymptotic Giant Branch (AGB) stars located in the Galactic bulge. Methods: A homogeneous and…
The earliest phases of the chemical evolution of our Galaxy are analysed in the light of the recent VLT results (concerning abundance patterns in the most metal-poor stars of the Galactic halo) and of stellar nucleosynthesis calculations.…
The stellar evolution of lithium-rich (Li-rich) giant stars at very low metallicities remains largely unexplored to date. Using two recent large LAMOST catalogues of field, low-mass giant stars (both Li-rich and Li-poor) with metallicities…
The primordial abundances of Deuterium, he4, and li7 are crucial to determination of the baryon density of the Universe in the framework of standard Big Bang nucleosynthesis (BBN). li6 which is only produced in tiny quantities and it is…
We previously explored the circumstellar effects on the Rb and Zr abundances in massive Galactic O-rich AGB stars. Here we are interested in the role of the extended atmosphere in the case of Li and Ca. Li is an important indicator of HBB…
We follow the chemical evolution of the Galaxy for elements from Ba to Eu, using an evolutionary model suitable to reproduce a large set of Galactic (local and non local) and extragalactic constraints. Input stellar yields for neutron-rich…
Precise studies on the Galactic bulge, halo, thick disk, and globular clusters require stellar models with alpha enhancement and various He contents. For this purpose we complement existing PARSEC (PAdova-TRieste Stellar Evolution Code)…
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…
We compute the chemical evolution of the Galactic bulge in the context of an inside-out model for the formation of the Milky Way. The model contains updated stellar yields from massive stars. The main purpose of the paper is to compare the…