Related papers: Str\"omgren metallicities for intermediate-age and…

The recent Gaia Data Release 1 of stellar parallaxes provides ample opportunity to find metal-poor main-sequence stars with precise parallaxes. We select 21 such stars with parallax uncertainties better than $\sigma_\pi/\pi\leq0.10$ and…

The effect of metallicity on the granulation activity in stars is still poorly understood. Available spectroscopic parameters from the updated APOGEE-\textit{Kepler} catalog, coupled with high-precision photometric observations from NASA's…

We present measurements of ages, metallicities, and [alpha/Fe] ratios for 16 globular clusters (GC) in NGC 147, NGC 185, and NGC 205 and of the central regions of the diffuse galaxy light in NGC 185, and NGC 205. Our results are based on…

Using a large SDSS galaxy group catalogue, we study how the stellar ages and metallicities of central and satellite galaxies depend on stellar mass and halo mass. We find that satellites are older and metal-richer than centrals of the same…

We present preliminary results from our on-going survey of Galactic globular clusters relative ages. The investigation is based on V,I images obtained at the ESO and La Palma telescopes, which make up the largest homogenous photometric…

We use the Stetson, HST, and Gaia DR3 data sets for 22 Galactic globular clusters to select their members and fit their CMDs with isochrones from DSED and BaSTI for $[\alpha/$Fe$]=+0.4$ and an adopted helium mass fraction $Y$. As a result,…

We infer stellar metallicity and abundance ratio gradients for a sample of red galaxies in the Sloan Digital Sky Survey (SDSS) Main galaxy sample. Because this sample does not have multiple spectra at various radii in a single galaxy, we…

We present the results of a study utilising ultra-deep, rest-frame UV, spectroscopy to quantify the relationship between stellar mass and stellar metallicity for 681 star-forming galaxies at $2.5<z<5.0$ ($\langle z \rangle = 3.5 \pm 0.6$)…

Estimates of the [O/H] metallicity of the star-forming gas in a sample of 66 CFRS galaxies between 0.47 < z < 0.92 have been made based on the flux ratios of bright emission lines. Most galaxies (> 75%) have the [O/H] ~ 8.9 metallicities…

We use the most homogeneous $Geneva$ seven-colour photometric system to derive new metallicity calibrations for early A- to K-type stars that cover both, dwarf stars and giants. The calibrations are based on several spectroscopic data sets…

We quantified and calibrated the metallicity and temperature sensitivities of colors derived from nine Wide Field Camera 3 (WFC3) filters aboard the Hubble Space Telescope using Dartmouth isochrones and Kurucz atmospheres models. The…

Very metal-poor halo stars are the best candidates for being among the oldest objects in our Galaxy. Samples of halo stars with age determination and detailed chemical composition measurements provide key information for constraining the…

(ABRIDGED) We assess the systematic uncertainties in (young) cluster age, mass, and - to a lesser extent - extinction and metallicity determinations, based on broad-band imaging observations with the Hubble Space Telescope. Our aim here is…

The age calibration of the Washington deltaT1 index is mainly used to estimate ages of star clusters older than 1 Gyr, no age-metallicity degeneracy effect is considered. We have profusely exploited synthetic T1 versus C-T1 colour magnitude…

We present results of age determination based on the standard procedure of isochrone fitting for about 600 star clusters younger than about 1.2 Gyr from the central parts of the LMC. Comparison of age distributions of star clusters from the…

We present a new theoretical calibration of the Stroemgren metallicity index hk by using alpha-enhanced evolutionary models transformed into the observational plane by using atmosphere models with the same chemical mixture. We apply the new…

We study azimuthal variations in the mean stellar metallicity, <[Fe/H]>, in a self-consistent, isolated simulation in which all stars form out of gas. We find <[Fe/H]> variations comparable to those observed in the Milky Way and which are…

We develop a method to estimate photometric metallicities by simultaneously fitting the dereddened colors u-g, g-r, r-i and i-z from the SDSS with those predicted by the metallicity-dependent stellar loci. The method is tested with a…

Accurate stellar parameters of stars in open clusters can help constrain models of stellar structure and evolution. Here we wish to determine the age and metallicity content of the open cluster NGC 2506. To this end we investigated three…

Using Monte Carlo simulations of globular clusters we developed a method separating metallicity effects from age effects on observed integrated ugriz colors. We demonstrate that these colors do not evolve with time significantly after an…