The VMC survey – XXXV. model fitting of LMC Cepheid light curves

Abstract

ABSTRACT We present the results of the light curve model fitting technique applied to optical and near-infrared photometric data for a sample of 18 Classical Cepheids (11 fundamentals and 7 first overtones) in the Large Magellanic Cloud (LMC). We use optical photometry from the OGLE III data base and near-infrared photometry obtained by the European Southern Observatory public survey ‘VISTA near-infrared survey of the Magellanic Clouds system’. Iso-periodic non-linear convective model sequences have been computed for each selected Cepheid in order to reproduce the multifilter light-curve amplitudes and shape details. The inferred individual distances provide an intrinsic weighted mean value for the LMC distance modulus of μ0 = 18.56 mag with a standard deviation of 0.13 mag. We derive also the Period–Radius, the Period–Luminosity, and the Period–Wesenheit relations that are consistent with similar relations in the literature. The intrinsic masses and luminosities of the best-fitting models show that all the investigated pulsators are brighter than the predictions of the canonical evolutionary mass–luminosity relation, suggesting a significant efficiency of non-canonical phenomena, such as overshooting, mass-loss, and/or rotation.