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Quark mass effects to σ(e^+e^- -> hadrons) at O(α_s^3)

K. G. Chetyrkin·R. Harlander·J. H. Kuehn
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Abstract

The calculation of the quartic mass terms at order α_s^3 to the hadronic R ratio is described. It is based on the operator product expansion for the quark current correlator, combined with an application of the renormalization group equation.

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K. G. Chetyrkin, R. Harlander, J. H. Kuehn. 1999-10-14. Quark mass effects to σ(e^+e^- -> hadrons) at O(α_s^3). https://arxiv.org/abs/hep-ph/9910345

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