The Distance to the Large Magellanic Cloud from the Eclipsing Binary HV 2274

The distance to the Large Magellanic Cloud (LMC) is crucial for the calibration of the cosmic distance scale. We derive a distance to the LMC based on an analysis of ground-based photometry and Hubble Space Telescope (HST)-based spectroscopy and spectrophotometry of the LMC-eclipsing binary system HV 2274. Analysis of the optical light curve and the HST/Goddard High-Resolution Spectrograph, radial velocity curve provides the masses and radii of the binary components. Analysis of the HST/Faint Object Spectrograph, UV/optical spectrophotometry provides the temperatures of the component stars and the interstellar extinction of the system. When combined, these data yield a distance to the binary system. After correcting for the location of HV 2274 with respect to the center of the LMC, we find dLMC = 45.7 ± 1.6 kpc or (V0-Mv)LMC = 18.30 ± 0.07 mag. This result, which is immune to the metallicity-induced zero-point uncertainties that have plagued other techniques, lends strong support to the "short" LMC distance scale as derived from a number of independent methods.

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