2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/206426We improve on a recent determination of alpha_s from Gamma(Upsilon(1S)-->X gamma)/Gamma(Upsilon(1S)-->X) with CLEO data by taking into account color octet contributions and avoiding any model dependence in the extraction. We obtain alpha_s(M_Upsilon(1S))= 0.184+0.015-0.014, which corresponds to alpha_s(M_Z)=0.119+0.006-0.005.11 pages. v2: One reference added. v3: Minor modification in an error estimate. Journal versionHigh Energy Physics - PhenomenologyHigh Energy Physics - ExperimentHigh Energy Physics - Latticetext