相关论文: Basic physical parameters of a selected sample of …

The fraction of binary stars (fb) is one of most valuable tool to probe the star formation and evolution of multiple systems in the Galaxy. We focus on the relationship between fb and stellar metallicity ([Fe/H]) by employing the…

Homogeneous photometric data (Johnson V, B-V, V-K, Cousins V-I and Stromgren b-y), radial velocities, and abundances of Fe, O, Mg, Si, Ca, Ti, Cr and Ni are presented for 99 stars with high precision parallaxes measured by the Hipparcos…

One of the greatest difficulties in astrophysics is the determination of the fundamental stellar parameters (FSPs), one of which is the initial mass fraction of helium (Y). However, given that Y can be measured spectroscopically in only a…

We present a high-resolution spectroscopic analysis of two samples of evolved stars selected in the field and in the intermediate-age open cluster IC 4651, for which detailed measurements of chemical composition were made in the last few…

A previous study of correlations between element abundance ratios, [X/Fe], and ages of solar twin stars is extended to include Sc, Mn, Cu, and Ba. HARPS spectra with S/N > 600 are used to derive very precise (+/- 0.01 dex) differential…

We measure the relationship between stellar mass and stellar metallicity, the stellar mass--metallicity relation (MZR), for 1336 star-forming galaxies at $1.6\le z\le3.0$ (<z>=2.2) using rest-frame far-ultraviolet spectra from the…

Estimating age distributions, or star formation histories, of stellar populations in the Milky Way is important in order to study the evolution of trends in elemental abundances and kinematics. We build on previous work to develop an…

We have estimated fundamental parameters for a sample of co-moving stars observed by $Gaia$ and identified by Oh et al. (2017). We matched the $Gaia$ observations to the 2MASS and WISE catalogs and fit MIST isochrones to the data, deriving…

For studies of Galactic evolution, the accurate characterization of stars in terms of their evolutionary stage and population membership is of fundamental importance. A standard approach relies on extracting this information from stellar…

We present precise photometric estimates of stellar parameters, including effective temperature, metallicity, luminosity classification, distance, and stellar age, for nearly 26 million stars using the methodology developed in the first…

We present a new version of the compiled catalogue of nearby stars for which was published the spectoscopically determined effective temperatures, surface gravities, and abundances of iron, magnesium, calcium, silicon, and titanium.…

Transiting planets around stars are discovered mostly through photometric surveys. Unlike radial velocity surveys, photometric surveys do not tend to target slow rotators, inactive or metal-rich stars. Nevertheless, we suspect that…

In the past years we have made great efforts to reduce the statistical and systematic uncertainties in stellar parameter and chemical abundance determinations of early B-type stars. Both the construction of robust model atoms for non-LTE…

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…

New ages are computed for stars in the Solar Neighbourhood from the Edvardsson et al. (1993) data set. Distances derived from the Hipparcos parallaxes were adopted to obtain reliable ages (uncertainty less than 12%) for a subset of stars.…

Aims. A sample of early B-type stars in OB associations and the field within the solar neighbourhood is studied comprehensively. Present-day abundances for the astrophysically most interesting chemical elements are derived. Methods.…

The entire evolution of the Milky Way, including its mass-assembly and star-formation history, is imprinted onto the chemo-dynamical distribution function of its member stars, f(x, v, [X/H]), in the multi-dimensional phase space spanned by…

Long-slit spectra have been obtained with the Keck telescope for a sample of 11 early-type galaxies covering a wide range in luminosity and hence mass. Rotation velocity and velocity dispersions, together with 19 Lick line-strength…

With the advent of dedicated photometric space missions, the ability to rapidly process huge catalogues of stars has become paramount. Bellinger and Angelou et al. (2016) recently introduced a new method based on machine learning for…

ABRIDGED: METHODS: We have conducted a high-resolution spectroscopic study of 714 F and G dwarf and subgiant stars in the Solar neighbourhood. The star sample has been kinematically selected to trace the Galactic thin and thick disks to…