Eclipsing Binary Stars In The Magellanic Clouds

Within the next few years eclipsing binaries should yield primary distance measurements for the Magellanic Clouds as well as provide tests of theoretical low-metallicity stellar models. Key Words : eclipsing binary stars, Magellanic Clouds, stellar evolution, distance indicators I. INTRODUCTION Eclipsing binaries in the Magellanic Clouds are currently of interest: 1) For tests of models of stellar structure and evolution at low metallicity (Milky Way, z¸0.020; LMC, z¸0.008; SMC, z¸0.004), and 2) As primary distance indicators. Masses and radii for comparison with theoretical models are derived from radial-velocity and differential light curves. Luminosities and hence distances come from coupling the stellar surface areas with surface fluxes determined from absolute photometry and spectrophotometry. As explained below, only excellent data will yield worthwhile accuracy, but with modern instruments and detectors this should with care be achievable for brighter systems in the Clouds. T..