相关论文: The mass discrepancy problem in O stars of solar m…
Context. The "mass discrepancy" in massive O stars represents a long-standing problem in stellar astrophysics with far-reaching implications for the chemical and dynamical feedback in galaxies. Aims. Our goal is to investigate this mass…
The Cepheid mass discrepancy, the difference between mass estimates from stellar pulsation and stellar evolution models, is a long standing challenge for the understanding of stellar astrophysics. We discuss the current state of the mass…
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…
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…
Metallicity is one of the crucial factors that determine stellar evolution. To characterize the properties of stellar populations one needs to know the fraction of stars forming at different metallicities. Knowing how this fraction evolves…
The history of the formation and evolution of the Milky Way Galaxy is found in the spatial distribution, kinematics, age and chemical abundance distributions of long-lived stars. From this fossil record one can in principle extract the star…
Thanks to their usefulness in various fields of astrophysics (e.g. mixing processes in stars, chemical evolution of galaxies), the last few years have witnessed a large increase in the amount of abundance data for early-type stars. Two…
Massive stars play a key role in the evolution of the Universe. Our goal is to compare observed and predicted properties of single Galactic O stars to identify and constrain uncertain physical parameters and processes in stellar evolution…
The formation of stars above about twenty solar masses and their apparently high multiplicity remain heavily debated subjects in astrophysics. We have performed a vast high-resolution radial velocity spectroscopic survey of about 250 O- and…
Estimating ages for stars is difficult at best, but Galactic problems have their own requirements that go beyond those for other areas of astrophysics. As in other areas, asteroseismology is helping, and in this review I discuss some of the…
Using asteroseismic data from the Kepler satellite, we explore the systematic uncertainties arising from changes in the input physics used when constructing evolution models of solar-type stars. We assess the impact of including atomic…
The growing database of exoplanets have shown us the statistical characteristics of various exoplanet populations, providing insight towards their origins. Observational evidence suggests that the process by which gas giants are conceived…
Low-mass stars play a key role in many different areas of astrophysics. In this article, I provide a brief overview of the evolution of low-mass stars, and discuss some of the uncertainties and problems currently affecting low-mass stellar…
Ancient, long-lived stars remain present in all components of our home galaxy, the Milky Way. Born a few hundred million after the Big Bang and during a time that marked the very beginning of the chemical evolution, these stars display very…
The evolution of C and O abundances in the Milky Way can impose strong constraints on stellar nucleosynthesis and help understanding the formation and evolution of our Galaxy. The aim is to review the measured C and O abundances in the disk…
We show that different stellar-mass estimation methods yield overall mass scales that disagree by factors up to ~2 for the z=0 galaxy population, and more importantly, relative mass scales that sometimes disagree by factors >~3 between…
In this last decade, our knowledge of evolutionary and structural properties of stars of different mass and chemical composition is significantly improved. This result has been achieved as a consequence of our improved capability in…
We review the yields of intermediate mass elements (from C to Zn) from massive stars and their associated uncertainties, in the light of recent theoretical results. We consider the role of those yields for our understanding of the chemical…
The observed star formation rate of the Milky Way can be explained by applying a metallicity-dependent factor to convert CO luminosity to molecular gas mass and a star formation efficiency per free-fall time that depends on the virial…
We consider some aspects of the evolution of massive stars which can only be elucidated by means of "indirect" observations, i.e. measurements of the effects of massive stars on their environments. We discuss in detail the early evolution…