相关论文: Age-luminosity relations for low-mass metal-poor s…

This study is aimed at identifying possible low-mass and sub-stellar companions to stars with well-determined metallicities. We investigate the multiplicity of metal-poor stars along with its impact on formation processes in the conditions…

In many evolutionary stages, low- and intermediate-mass stars show signs of mixing of the surface material with material from the interior. To account for all the details revealed by the observations it is necessary to include non-standard…

Cosmic History has witnessed the lives and deaths of multiple generations of massive stars, all of them invigorating their host galaxies with ionizing photons, kinetic energy, fresh material and stellar-mass black holes. Ubiquitous engines…

We have performed deep imaging of a diverse sample of 26 low surface brightness galaxies (LSBGs) in the optical and the near-infrared. Using stellar population synthesis models, we find that it is possible to place constraints on the ratio…

We present dense grids of stellar models suitable for comparison with observable quantities measured with great precision, such as those derived from binary systems or planet-hosting stars. We computed new Geneva models without rotation at…

Observations show that galaxies follow a mass-metallicity relation over a wide range of masses. One currently favoured explanation is that less massive galaxies are less able to retain the gas and stellar ejecta and thus may lose the…

We present new evolutionary stellar models suitable for old Population I clusters, discussing both the consequences of the most recent improvements in the input physics and the effect of element diffusion within the stellar structures.…

We study the age and metallicity distribution function (MDF) of metal-poor stars in the Milky Way halo as a function of galactocentric radius by combining N-body simulations and semi-analytical methods. We find that the oldest stars…

This paper discusses low mass, metal poor stars, presenting new evolutionary computations which take into account the inward diffusion of both He and heavy elements during the H burning phase. The investigation has been extended to He…

In this review we outline the major points of ab-initio cosmological models focusing on some galaxy evolution unresolved problems. In particular our knowledge of the star formation rate which leads galaxy evolution, i.e. luminosity, colors…

With a sample of 22 metal-poor stars, we demonstrate that the heavy element abundance pattern (Z > 55) is the same as the r-process contributions to the solar nebula. This bolsters the results of previous studies that there is a universal…

In this paper, we are exploring the properties of old, metal-poor globular clusters in galaxies. We investigate whether their properties are related to the properties of their host galaxies, and whether we can constrain their formation. The…

Based on a new large, homogeneous photometric database of 35 Galactic globular clusters (GGCs), a set of distance and reddening independent relative age indicators has been measured. The observed D(V-I)_2.5 and D(V)(HB-TO) vs. metallicity…

(shortened) The first couple of stellar generations may have been massive, of order 100 Msun, and to have played a dominant role in galaxy formation and the chemical enrichment of the early Universe. Some fraction of these objects may have…

The star formation, mass assembly and chemical enrichment histories of galaxies, and their present distributions of dark matter, remain encoded in their stellar populations. Distinguishing the actual distribution functions of stellar age,…

Young populations at Z<Zo are being examined to understand the role of metallicity in the first phases of stellar evolution. For the analysis it is necessary to assign mass and age to Pre--Main Sequence (PMS) stars. While it is well known…

A review is presented of some of the ingredients, assumptions and techniques that are used in the computation of the structure and evolution of low-mass stars. Emphasis is placed on several ingredients which are still subject to…

Metal-poor stars are key for studying the formation and evolution of the Galaxy. Evidence of the early mergers that built up the Galaxy remains in the distributions of abundances, kinematics, and orbital parameters of its stars. Several…

Context. Metal-poor massive stars are supposed to be progenitors of certain supernovae, gamma-ray bursts and compact object mergers, potentially contributing to the early epochs of the Universe with their strong ionizing radiation. However,…

Open clusters (OC) of 1-3 Gyr age contain intermediate-to-low-mass stars in evolutionary phases of multiple relevance to understanding Li evolution. Stars leaving the main sequence (MS) from the hot side of the Lithium dip (LD) at a fixed…