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arXiv · 1110.6859

Lambda_msbar from the static potential for QCD with n_f=2 dynamical quark flavors

ETM Collaboration·Karl Jansen·Felix Karbstein·Attila Nagy·Marc Wagner
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Abstract

We determine Lambda_msbar for QCD with n_f=2 dynamical quark flavors by fitting the Q-Q-bar static potential known analytically in the perturbative regime up to terms of O(alpha_s^4) and ~alpha_s^4 ln(alpha_s) to corresponding results obtained from lattice simulations. This has become possible, due to recent advances in both perturbative calculations, namely the determination and publication of the last missing contribution to the Q-Q-bar static potential at O(alpha_s^4), and lattice simulations with n_f=2 dynamical quark flavors performed at the rather fine lattice spacing of a~0.042 fm. Imposing conservative error estimates we obtain Lambda_msbar=315(30) MeV.

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ETM Collaboration, Karl Jansen, Felix Karbstein, Attila Nagy, Marc Wagner. 2011-11-21. Lambda_msbar from the static potential for QCD with n_f=2 dynamical quark flavors. https://doi.org/10.1007/jhep01(2012)025

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