Related papers: Theoretical models for Bump Cepheids

We investigate a selected sample of Galactic classical Cepheids with available distance and reddening estimates in the framework of the theoretical scenario provided by pulsation models, computed with metal abundance Z=0.02, helium content…

We analyse photometry of $\sim$2000 Galactic Cepheids available in the OGLE Collection of Variable Stars. We analyse both Galactic disk and Galactic bulge fields; stars classified both as single- and multi-periodic. Our goal was to search…

Infrared and optical absolute magnitudes are derived for the type II Cepheids kappa Pav and VY Pyx from revised Hipparcos parallaxes and for kappa Pav, V553 Cen and SW Tau from pulsation parallaxes. Phase-corrected JHK mags are given for…

The circumstellar envelopes (CSE) of Cepheids are still not well characterized despite their potential impact on distance determination via both the period-luminosity relation and the parallax-of-pulsation method. This paper aims to…

Context. The Cepheid mass discrepancy, the difference between masses predicted from stellar evolution and stellar pulsation calculations, is a challenge for the understanding of stellar astrophysics. Recent models of the eclipsing binary…

We present new accurate Period-Luminosity (PL) and Period-Wesenheit (PW) relations in the V,J,Ks bands based on a sample of more than 4500 Cepheids in the Large Magellanic Cloud (LMC) whose photometry was obtained in the context of the…

The rationale behind recent calibrations of the Cepheid PL relation using the Wesenheit formulation is reviewed and reanalyzed, and it is shown that recent conclusions regarding a possible change in slope of the PL relation for short-period…

We analyze Galactic, Large Magellanic Cloud and Small Magellanic Cloud Cepheids and RR Lyrae variables in terms of period-color (PC) and amplitude-color (AC) diagrams at the phases of maximum and minimum light. We compiled Galactic Cepheids…

We present the comparison between theoretical and empirical PL relations in V and I bands for the Large Magellanic Cloud. We found that, within the current intrinsic dispersions, theoretical predictions are in remarkable agreement with…

We present the first part of a new catalog of variable stars (OIII-CVS) compiled from the data collected in the course of the third phase of the Optical Gravitational Lensing Experiment (OGLE-III). In this paper we describe the catalog of…

The appearance of blue loops in the evolutionary tracks of intermediate-mass core He-burning stars is essential for explaining the observed characteristics of Cepheids. The blue loops for lower mass Cepheids cannot always be reproduced when…

The recent discovery, based on a search of public OGLE data, of Be star candidates in the Small Magellanic Cloud showing spectacular photometric variations (Mennickent et al. 2002), has motivated further analysis of their light curves. Here…

In this paper, we construct full amplitude non-linear hydrodynamical models of fundamental mode Galactic Cepheids and analyze the resulting theoretical period-colour and amplitude-colour relations at maximum, mean and minimum light. These…

The Cepheid Leavitt Law (LL), also known as the Period-Luminosity relation, is a crucial tool for assembling the cosmic distance ladder. By combining data from the OGLE-IV catalogue with mid-infrared photometry from the Spitzer Space…

We show that the luminosity dependence of the red clump stars on age and metallicity can cause a difference of up to < ~0.6 mag in the mean absolute I magnitude of the red clump between different stellar populations. We show that this…

Approximately four thousand light curves of red variable stars in the LMC were selected from the 2.3-years duration MOA database by a period analysis using the Phase Dispersion Minimization method. Their optical features (amplitudes,…

We present the first application of mid-infrared Period-Luminosity relations to the determination of a Cepheid distance beyond the Magellanic Clouds. Using archival IRAC imaging data on NGC 6822 from Spitzer we were able to measure…

The LMC is ideal for studying the co-evolution of planetary nebulae (PNe) and their central stars, in that the debilitating uncertainties of the Galactic PN distance scale and selection biases from attenuation by interstellar dust do not…

Classical Cepheids are a cornerstone class of pulsators, fundamental to testing stellar evolution and pulsation theories. Their secular period changes, characterized through $O-C$ (Observed minus Calculated) diagrams, offer valuable…

(Abridged) I cross-correlate the OGLE database of Cepheids in the Large and Small Magellanic Clouds (MCs) with the second incremental release of the 2MASS JHK survey, and the DENIS IJK point source catalog towards the MCs. Of the 3384…