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arXiv · hep-ph/9707474

$α_s(m_Z)$ from tau decays with matching conditions at three loops

German Rodrigo·Antonio Pich·Arcadi Santamaria
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Abstract

Using the recent four-loop calculations of the QCD beta-function and the three-loop matching coefficients we study the induced error in $α_s(m_Z)$ obtained from $α_s(m_tau)$ due to the evolution procedure. We show that, when consistent matching and running is used at this order, these errors are pushed below 0.0005 in $α_s(m_Z)$.

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German Rodrigo, Antonio Pich, Arcadi Santamaria. 1997-07-25. $α_s(m_Z)$ from tau decays with matching conditions at three loops. https://doi.org/10.1016/s0370-2693(98)00219-6

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