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arXiv · 1201.5770

The strong running coupling at $\tau$ and $Z_0$ mass scales from lattice QCD

B. Blossier·Ph. Boucaud·M. Brinet·F. De Soto·X. Du·V. Morenas·O. Pène·K. Petrov·J. Rodríguez-Quintero
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Abstract

This letter reports on the first computation, from data obtained in lattice QCD with $u,d,s$ and $c$ quarks in the sea, of the running strong coupling via the ghost-gluon coupling renormalized in the MOM Taylor scheme. We provide with estimates of $\ams(m_\tau^2)$ and $\ams(m_Z^2)$ in very good agreement with experimental results. Including a dynamical c quark makes safer the needed running of $\ams$.

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B. Blossier, Ph. Boucaud, M. Brinet, F. De Soto, X. Du, V. Morenas, O. Pène, K. Petrov, J. Rodríguez-Quintero. 2012-01-27. The strong running coupling at $\tau$ and $Z_0$ mass scales from lattice QCD. https://doi.org/10.1103/physrevlett.108.262002

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