相关论文: The early phases of Milky Way's chemical evolution
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…
The early chemical evolution of the Galaxy and the Universe is vital to our understanding of a host of astrophysical phenomena. Since the most metal-poor Galactic stars (with metallicities down to [Fe/H]\sim-5.5) are relics from the…
In this paper we study the very early phases of the evolution of our Galaxy by means of a chemical evolution model which reproduces most of the observational constraints in the solar vicinity and in the disk. We have restricted our analysis…
The present day chemical and dynamical properties of the Milky Way bear the imprint of the Galaxy's formation and evolutionary history. One of the most enduring and critical debates surrounding Galactic evolution is that regarding the…
Recent dynamical analysis based on Gaia data have revealed major accretion events in Milky Way's history. Nevertheless, our understanding of the primordial Galaxy is hindered because the bona fide identification of the most metal-poor and…
The cosmic microwave background and the cosmic expansion can be interpreted as evidence that the Universe underwent an extremely hot and dense phase about 14 Gyr ago. The nucleosynthesis computations tell us that the Universe emerged from…
Context. The recent detection of nitrogen-enhanced, metal-poor galaxies at high redshift by the James Webb Space Telescope has sparked renewed interest in exploring the chemical evolution of carbon, nitrogen, and oxygen (the CNO elements)…
Stellar chemical element ratios have well-defined systematic trends as a function of abundance, with an excellent correlation of these trends with stellar populations defined kinematically. This is remarkable, and has significant…
This paper presents theoretical star formation and chemical enrichment histories for the stellar halo of the Milky Way based on new chemodynamical modeling. The goal of this study is to assess the extent to which metal-poor stars in the…
Initial conditions are set by Big bang nucleosynthesis from which we know that 90 per cent of baryons are dark and have essentially unknown chemical composition. In our own Galaxy, there are many clues from individual stars in different…
We study the chemical evolution and formation of the Galactic halo through the analysis of its stellar metallicity distribution function and some key elemental abundance patterns. Starting from the two-infall model for the Galaxy, which…
We present preliminary results of stellar structure and nucleosynthesis calculations for some early stars. The study (still in progress) seeks to explore the expected chemical signatures of second generation low- and intermediate-mass stars…
Adopting a single-zone framework, with accretion of primordial gas on a free-fall timescale, the chemical evolution of the Galactic bulge is calculated, assuming (i) a corresponding rapid timescale for star formation, and (ii) an initial…
A short overview is presented of several topics concerning the evolution of the Milky Way (MW) in a cosmological context. In particular, the metallicity distribution of the MW halo is derived analytically and the halo metallicity and…
Status quo and perspectives of standard chemical evolution models of Local Group galaxies are summarized, discussing what we have learnt from them, what we know we have not learnt yet, and what I think we will learn in the near future. It…
An early history of metal enrichment in the Galactic halo is studied. We investigate chemical inhomogeneity by using a stochastic chemical evolution model. The model confronts with metallicity distribution function of long-lived halo stars…
The massive First Stars (the first ones to contribute to the chemical enrichment of the Universe due to their short lifetimes) are long dead, and even though efforts to directly observe them in high redshift galaxies are underway, a step…
We present numerical simulations to describe the nucleosynthesis and evolution of pre-Galactic clouds in a model which is motivated by cold dark matter simulations of hierarchical galaxy formation. We adopt a SN-induced star-formation…
We investigate the chemical evolution of the Milky Way disc exploring various schemes of recent (last several Gyr) star formation episodes, as reported in recent observational works. We use a semi-analytical model with parametrized radial…
Near-field observations may provide tight constraints - i.e. "boundary conditions" - on any model of structure formation in the Universe. Detailed observational data have long been available for the Milky Way (e.g. Freeman $\&$…