OGLE 2004–BLG–254: a K3 III Galactic bulge giant spatially resolved by a single microlens

Aims. We present an analysis of OGLE 2004–BLG–254, a high-magnification () and relatively short duration ( days) microlensing event in which the source star, a Bulge K-giant, has been spatially resolved by a point-like lens. We seek to determine the lens and source distance, and provide a measurement of the linear limb-darkening coefficients of the source star in the I and R bands. We discuss the derived values of the latter and compare them to the classical theoretical laws, and furthermore examine the cases of already published microlensed GK-giants limb-darkening measurements.