Related papers: Stellar models and Hyades: the Hipparcos test
A new set of stellar models in the mass range 1.2 to 9 $M_{\odot}$ is presented. The adopted chemical compositions cover the typical galactic values, namely $0.0001 \le Z \le 0.02$ and $0.23 \le Y \le 0.28$. A comparison among the most…
Stellar models with masses ranging from 0.5 to $1.3~M_\odot$ were constructed in order to compare to young cluster observations of Li and of rotation velocities. The amount of Li depletion in cool stars is sensitive to the amount of…
The discrepancy between the Pleiades cluster distance based on Hipparcos parallaxes and main sequence fitting is investigated on the basis of Stromgren photometry of F-type stars. Field stars with the same metallicity as the Pleiades have…
We compare the absolute visual magnitude of the majority of bright O stars in the sky as predicted from their spectral type with the absolute magnitude calculated from their apparent magnitude and the Hipparcos parallax. We find that many…
Astrophysical models of binary-black hole mergers in the Universe require a significant fraction of stellar-mass black holes (BHs) to receive negligible natal kicks to explain the gravitational wave detections. This implies that BHs should…
In this review, I will discuss a few problems which point to the need for improved stellar evolution models of halo stars. Current stellar evolution models do not match the observed $^7$Li abundance patterns, suggesting that the input…
Stellar models provide a vital basis for many aspects of astronomy and astrophysics. Recent advances in observational astronomy -- through asteroseismology, precision photometry, high-resolution spectroscopy, and large-scale surveys -- are…
During the last decade, the understanding of fine features of the structure and evolution of stars has become possible as a result of enormous progress made in the acquisition of high-quality observational and experimental data and of new…
We supplement current evolutionary computations concerning Magellanic Cloud stars by exploring the evolutionary behavior of canonical stellar models (i.e.,with inefficient core overshooting) with metallicities suitable for stars in the…
In the first of a new series of papers on open cluster distances, we use updated stellar evolution models to construct an isochrone appropriate for the Hyades, and compare it with the Hyades eclipsing binary system vB 22. We find that the…
Hipparcos parallaxes fix distances to individual stars in the Hyades cluster with an accuracy of 6%. We use the Hipparcos (and Tycho-2) proper motions, which have a larger relative precision than the trigonometric parallaxes, to derive ~3…
{This paper presents detailed analysis and modelisation of the star HD17051 (alias $\iota$ Hor), which appears as a specially interesting case among exoplanet host stars. As most of these stars, $\iota$ Hor presents a metallicity excess…
We combine recently computed models of stellar evolution using a new treatment of rotation with a Bayesian statistical framework to constrain the ages and other properties of early-type stars. We find good agreement for early-type stars and…
Calibration and benchmarking of evolutionary and atmospheric models is essential for the study of low-mass stars and brown dwarfs, as for isolated objects these models are the only way to determine basic parameters like mass and age. The…
We present deep and precise photometry (F435, F625W, F658N) of Omega Cen collected with the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST). We have identified ~ 6,500 white dwarf (WD) candidates, and the ratio…
The tension between the Hipparcos parallax of the Pleiades and other independent distance estimates continues even after the new reduction of the Hipparcos astrometric data and the development of a new geometric distance measurement for the…
Stellar population synthesis (SPS) models are a key tool for deriving the age, metallicity, radial velocity and reddening of star clusters from their integrated spectra. Using a sample of 129 star clusters with high-quality spectra, we…
The Kepler and TESS space missions significantly expanded our knowledge of what types of stars display flaring activity by recording a vast amount of super-flares from solar-like stars, as well as detecting flares from hotter stars of A-F…
This letter follows a recent claim that the Hipparcos parallax for Polaris could be too small by 2.5 mas. It examines in detail the Hipparcos epoch astrometric data for Polaris, as well as the viability of other observations that were put…
Since the release of the Hipparcos catalog in 1997, the distance to the Pleiades open cluster has been heavily debated. The distance obtained from Hipparcos and those by alternative methods differ by 10 to 15 %. As accurate stellar…