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Extraction of alpha_s from radiative Upsilon(1S) decays

Nora Brambilla·Xavier Garcia i Tormo·Joan Soto·Antonio Vairo
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Abstract

We 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.

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Nora Brambilla, Xavier Garcia i Tormo, Joan Soto, Antonio Vairo. 2007-03-29. Extraction of alpha_s from radiative Upsilon(1S) decays. https://doi.org/10.1103/physrevd.75.074014

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