Cluster AgeS Experiment: The Age and Distance of the Globular Cluster ω Centauri Determined from Observations of the Eclipsing Binary OGLEGC 17

We use photometric and spectroscopic observations of the detached eclipsing binary OGLEGC 17 to derive the masses, radii, and luminosities of the component stars, and we then use these estimates to calculate the age and distance of the globular cluster ω Cen. Age versus turnoff mass and age versus luminosity relations from Girardi et al. yield two independent estimates of the age, 9.1 < t < 16.7 Gyr and 12.9 < t < 18.5 Gyr. The distance and distance modulus derived by use of the infrared versus surface brightness relation are d = 5360 ± 300 pc and (m - M)V = 14.05 ± 0.11. Distances derived from our infrared surface brightness versus color relation and the Teff versus B-V color relation of Sekiguchi & Fukugita disagree by about 10%. Major improvements in the accuracy in estimated age and distance can be made with better measurements of the masses of the components of OGLEGC 17.

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