R ( s ) and Z decay in order α 4 s : complete results
نویسنده
چکیده
We report on our calculation of the order α4 s axial singlet contributions for the decay rates of the Z-boson as well as the vector singlet contribution to the cross section for electron-positron annihilation into hadrons. Together with recently finished O(α4 s ) calculations of the non-signlet corrections [1, 2], the new results directly lead us to the first complete O(α4 s ) predictions for the total hadronic decay rate of the Z-boson and the ratio R(s) = σ(e +e−→hadrons) σ(e+e−→μ+μ−) .
منابع مشابه
Complete QCD Corrections to Hadronic Z – Decays in Order α
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