Extraction of alpha(s) from radiative Upsilon(1S) decays

We improve on a recent determination of {alpha}{sub s} from {gamma}({upsilon}(1S){yields}{gamma}X)/{gamma}({upsilon}(1S){yields}X) with CLEO data by taking into account color octet contributions and avoiding any model dependence in the extraction. We obtain {alpha}{sub s}(M{sub {upsilon}}{sub (1S)})=0.184{sub -0.014}{sup +0.015}, which corresponds to {alpha}{sub s}(M{sub Z})=0.119{sub -0.005}{sup +0.006}.