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Accurate Determinations of $α_s$ from Realistic Lattice QCD

Q. Mason·H. D. Trottier·C. T. H. Davies·K. Foley·A. Gray·G. P. Lepage·M. Nobes·J. Shigemitsu
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Abstract

We obtain a new value for the QCD coupling constant by combining lattice QCD simulations with experimental data for hadron masses. Our lattice analysis is the first to: 1) include vacuum polarization effects from all three light-quark flavors (using MILC configurations); 2) include third-order terms in perturbation theory; 3) systematically estimate fourth and higher-order terms; 4) use an unambiguous lattice spacing; and 5) use an $\order(a^2)$-accurate QCD action. We use 28~different (but related) short-distance quantities to obtain $α_{\bar{\mathrm{MS}}}^{(5)}(M_Z) = 0.1170(12)$.

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Q. Mason, H. D. Trottier, C. T. H. Davies, K. Foley, A. Gray, G. P. Lepage, M. Nobes, J. Shigemitsu. 2005-06-30. Accurate Determinations of $α_s$ from Realistic Lattice QCD. https://doi.org/10.1103/physrevlett.95.052002

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