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arXiv · 1110.5829

Ghost-gluon coupling, power corrections and $Λ_{\bar{\rm MS}}$ from lattice QCD with a dynamical charm

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

This paper is a first report on the determination of $Λ_{\msbar}$ from lattice simulations with 2+1+1 twisted-mass dynamical flavours {\it via} the computation of the ghost-gluon coupling renormalized in the MOM Taylor scheme. We show this approach allows a very good control of the lattice artefacts and confirm the picture from previous works with quenched and ${\rm N}_f$=2 twisted-mass field configurations which prove the necessity to include non-perturbative power corrections in the description of the running. We provide with an estimate of $Λ_{\msbar}$ in very good agreement with experimental results. To our knowledge it is the first calculation with a dynamical charm quark which makes the running up to $α_s(M_Z)$ much safer.

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BibTeXRIS

B. Blossier, Ph. Boucaud, M. Brinet, F. De Soto, X. Du, M. Gravina, V. Morenas, O. Pène, K. Petrov, J. Rodríguez-Quintero. 2012-01-27. Ghost-gluon coupling, power corrections and $Λ_{\bar{\rm MS}}$ from lattice QCD with a dynamical charm. https://doi.org/10.1103/physrevd.85.034503

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