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arXiv · 0811.2059

Ghost-gluon running coupling, power corrections and the determination of $Λ_{\bar {\rm MS}}$

Ph. Boucaud·F. De Soto·J. P. Leroy·A. Le Yaouanc·J. Micheli·O. Pène·J. Rodríguez-Quintero
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Abstract

We compute a formula including OPE power corrections to describe the running of a QCD coupling non-perturbatively defined through the ghost and gluon dressing functions. This turns out to be rather accurate. We propose the ``{\it plateau}''-procedure to compute $Λ_{\bar{\rm MS}}$ from the lattice computation of the running coupling constant. We show a good agreement between the different methods which have been used to estimate $Λ_{\bar{\rm MS}}^{N_f=0}$. We argue that $Λ_{\bar{\rm MS}}$ or the strong coupling constant computed with different lattice spacings may be used to estimate the lattice spacing ratio.

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Ph. Boucaud, F. De Soto, J. P. Leroy, A. Le Yaouanc, J. Micheli, O. Pène, J. Rodríguez-Quintero. 2008-11-13. Ghost-gluon running coupling, power corrections and the determination of $Λ_{\bar {\rm MS}}$. https://doi.org/10.1103/physrevd.79.014508

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