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arXiv · 1210.3594

R(s) and Z decay in order α_s^4: complete results

P. A. Baikov·K. G. Chetyrkin·J. H. Kühn·J. Rittinger
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Abstract

We report on our calculation of the order α_s^4 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(α_s^4) calculations of the non-signlet corrections [1,2], the new results directly lead us to the first complete O(α_s^4) predictions for the total hadronic decay rate of the Z-boson and the ratio R(s).

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P. A. Baikov, K. G. Chetyrkin, J. H. Kühn, J. Rittinger. 2012-10-12. R(s) and Z decay in order α_s^4: complete results. https://arxiv.org/abs/1210.3594

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