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arXiv · 0807.1687

Update: Accurate Determinations of alpha_s from Realistic Lattice QCD

C. T. H. Davies·K. Hornbostel·I. D. Kendall·G. P. Lepage·C. McNeile·J. Shigemitsu·H. Trottier
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Abstract

We use lattice QCD simulations, with MILC configurations (including vacuum polarization from u, d, and s quarks), to update our previous determinations of the QCD coupling constant. Our new analysis uses results from 6 different lattice spacings and 12 different combinations of sea-quark masses to significantly reduce our previous errors. We also correct for finite-lattice-spacing errors in the scale setting, and for nonperturbative chiral corrections to the 22 short-distance quantities from which we extract the coupling. Our final result is alpha_V(7.5GeV,nf=3) = 0.2120(28), which is equivalent to alpha_msbar(M_Z,n_f=5)= 0.1183(8). We compare this with our previous result, which differs by one standard deviation.

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C. T. H. Davies, K. Hornbostel, I. D. Kendall, G. P. Lepage, C. McNeile, J. Shigemitsu, H. Trottier. 2008-12-14. Update: Accurate Determinations of alpha_s from Realistic Lattice QCD. https://doi.org/10.1103/physrevd.78.114507

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