Related papers: Cepheid Limb Darkening Models for the VLTI
Over the past decade, the Secret Lives of Cepheids (SLiC) program has been carried out at Villanova University to study aspects and behaviors of classical Cepheids that are still not well-understood. In this, the first of several planned…
An analysis of the observed characteristics of the Galactic Cepheid variables is carried out in the framework of their period-luminosity relation being used as a standard candle for distance measurement. The variation of the observed number…
In this paper we present an extended set of nonlinear convective pulsation models at varying the metallicity and DY/DZ ratio. The predicted instability strip and bolometric light curves are discussed by comparing the new models with our…
Optical-infrared interferometry can provide direct geometrical measurements of the radii of Cepheids and/or reveal unknown binary companions of these stars. Such information is of great importance for a proper calibration of…
Limb-darkening is fundamental in determining transit lightcurve shapes, and is typically modeled by a variety of laws that parametrize the intensity profile of the star that is being transited. Confronted with a transit lightcurve, some…
We briefly review the evolutionary status of the classical Cepheid variables, their structure, and the properties of the linear modes. Then we discuss the current status of the nonlinear hydrodynamical modelling, including modern adaptive…
Fourier decomposition is a well established technique used in stellar pulsation. However the quality of reconstructed light curves using this method is reduced when the observed data have uneven phase coverage. We use simulated annealing…
In spite of the relevance of Classical Cepheids as primary distance indicators, a general consensus on the dependence of the Period-Luminosity (PL) relation on the Cepheid chemical composition has not been achieved yet. From the theoretical…
Context. Recent observations of LMC Cepheids bring new constraints on the slope of the period-projection factor relation (hereafter Pp relation) that is currently used in the Baade-Wesselink (hereafter BW) method of distance determination.…
Y~Ophiuchi (Y~Oph) is a classical Cepheid reported to be as dim as a Cepheid of about half its pulsation period, and exhibits a low radial velocity and light-curves amplitude. Our objective is to conduct hydrodynamical pulsation modeling of…
Accurate radial velocities ($v_{\rm rad}$) of Cepheids are mandatory within the context of distance measurements via the Baade-Wesselink technique. The most common $v_{\rm rad}$ derivation method consists in cross-correlating the observed…
(ABRIDGED) We have applied the near-IR Barnes-Evans realization of the Baade-Wesselink method as calibrated by Fouque & Gieren (1997) to five metal-poor Cepheids with periods between 13 and 17 days in the Small Magellanic Cloud as well as…
One of the main endeavors of the field of exoplanetary sciences is the characterization of exoplanet atmospheres on a population level. The current method of choice to accomplish this task is transmission spectroscopy, where the apparent…
Stellar limb darkening is the observed variation in brightness of a star between its centre and edge (or limb) when viewed in the plane of the sky. Stellar brightness is maximal at the centre and then decreases radially and monotonically…
We present a light curve analysis of fundamental-mode Galactic and Large Magellanic Cloud (LMC) Cepheids based on the Fourier decomposition technique. We have compiled light curve data for Galactic and LMC Cepheids in optical ({\it VI}),…
We discuss the impact of possible differences in the slope of the Cepheid Period-Luminosity relation on the determination of extragalactic distances in the context of recent studies that suggest changes in this slope. We show that the…
We present a realization of the maximum-likelihood (ML) technique, which is one of the latest modifications of the Baade--Becker--Wesselink (BBW) method. Our approach is based on non-linear calibrations of the effective temperature and…
We develop a formulation of the Baade-Wesselink method which uses the Fourier coefficients of the observables. We derive an explicit, analytic expression to determine the mean radius from each Fourier order. The simplicity of this method…
Baade-Wesselink-type (BW) techniques enable geometric distance measurements of Cepheid variable stars in the Galaxy and the Magellanic clouds. The leading uncertainties involved concern projection factors required to translate observed…
For the nearby dwarf star alpha Cen B (K1 V), we present limb darkening predictions from a 3D hydro-dynamical radiative transfer model of its atmosphere. We first compare the results of this model to a standard Kurucz's atmosphere. Then we…