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An eclipsing-binary distance to the Large Magellanic Cloud accurate to two per cent
Determinations of the distances to eight long-period, late-type eclipsing systems in the Large Magellanic Cloud, composed of cool, giant stars, provide a firm base for a 3-per-cent determination of the Hubble constant.
The influence of chemical composition on the properties of Cepheid stars. II - The iron content ⋆
Context. The Cepheid period-luminosity (PL) relation is unquestionably one of the most powerful tools at our disposal for determining the extragalactic distance scale. While significant progress has
On the fine structure of the Cepheid metallicity gradient in the Galactic thin disk
We present homogeneous and accurate iron abundances for 42 Galactic Cepheids based on high resolution (R ~ 38 000) high signal-to-noise ratio (S/N ≥ 100) optical spectra collected with UVES at VLT
On the metallicity gradient of the Galactic disk
Aims. The iron abundance gradient in the Galactic stellar disk provides fundamental constraints on the chemical evolution of this important Galaxy component, however the spread around the mean slope
Relative Frequencies of Blue Stragglers in Galactic Globular Clusters: Constraints for the Formation Mechanisms*
We discuss the main properties of the Galactic globular cluster (GC)blue straggler stars (BSSs), as inferred from our new catalog containingnearly 3000 BSSs. The catalog has been extracted from
On a new theoretical framework for RR Lyrae stars I: the metallicity dependence
We present new nonlinear, time-dependent convective hydrodynamical models of RR Lyrae stars computed assuming a constant helium-to-metal enrichment ratio and a broad range in metal abundances
Classical Cepheid Pulsation Models. X. The Period-Age Relation
We present new period-age (PA) and period-age-color (PAC) relations for fundamental and first-overtone classical Cepheids. Current predictions rely on homogeneous sets of evolutionary and pulsation
The distance to the Galactic Centre based on Population-II Cepheids and RR Lyrae stars
Context. The distance to the Galactic centre (GC) is important for determining the distance scale in the Universe. The value derived by Eisenhauer et al. (2005) of 7.62 ± 0.32 kpc based on the orbit
Clustering of Local Group distances: publication bias or correlated measurements? IV. The Galactic Center
Aiming at deriving a statistically well-justified Galactic Center distance, $R_0$, and reducing any occurrence of publication bias, we compiled the most comprehensive and most complete database of
A Pulsational Distance to ω Centauri Based on Near-Infrared Period-Luminosity Relations of RR Lyrae Stars
We present new near-infrared (J and K) magnitudes for 114 RR Lyrae stars in the globular cluster ω Centauri (NGC 5139), which we combine with data from the literature to construct a sample of 180 RR