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arXiv · 1005.5290

Ghost-gluon coupling, power corrections and $Λ_{\overline {\rm MS}}$ from twisted-mass lattice QCD at Nf=2

B. Blossier·Ph. Boucaud·F. De soto·V. Morenas·M. Gravina·O. Pène·J. Rodríguez-Quintero
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Abstract

We present results concerning the non-perturbative evaluation of the ghost-gluon running QCD coupling constant from $N_f=2$ twisted-mass lattice calculations. A novel method for calibrating the lattice spacing, independent of the string tension and hadron spectrum is presented with results in agreement with previous estimates. The value of $Λ_{\overline{MS}}$ is computed from the running of the QCD coupling only after extrapolating to zero dynamical quark mass and after removing a non-perturbative OPE contribution that is assumed to be dominated by the dimension-two $\VEV{A^2}$ gluon condensate. The effect due to the dynamical quark mass in the determination of $\Lams$ is discussed.

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B. Blossier, Ph. Boucaud, F. De soto, V. Morenas, M. Gravina, O. Pène, J. Rodríguez-Quintero. 2010-05-28. Ghost-gluon coupling, power corrections and $Λ_{\overline {\rm MS}}$ from twisted-mass lattice QCD at Nf=2. https://doi.org/10.1103/physrevd.82.034510

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