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arXiv · hep-lat/0304004

High-Precision Lattice QCD Confronts Experiment

C. T. H. Davies·E. Follana·A. Gray·G. P. Lepage·Q. Mason·M. Nobes·J. Shigemitsu·H. D. Trottier·M. Wingate·C. Aubin·C. Bernard·T. Burch·C. DeTar·Steven Gottlieb·E. B. Gregory·U. M. Heller·J. E. Hetrick·J. Osborn·R. Sugar·D. Toussaint·M. Di Pierro·A. El-Khadra·A. S. Kronfeld·P. B. Mackenzie·D. Menscher·J. Simone
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Abstract

We argue that high-precision lattice QCD is now possible, for the first time, because of a new improved staggered quark discretization. We compare a wide variety of nonperturbative calculations in QCD with experiment, and find agreement to within statistical and systematic errors of 3% or less. We also present a new determination of alpha_msbar(Mz); we obtain 0.121(3). We discuss the implications of this breakthrough for phenomenology and, in particular, for heavy-quark physics.

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C. T. H. Davies, E. Follana, A. Gray, G. P. Lepage, Q. Mason, M. Nobes, J. Shigemitsu, H. D. Trottier, M. Wingate, C. Aubin, C. Bernard, T. Burch, C. DeTar, Steven Gottlieb, E. B. Gregory, U. M. Heller, J. E. Hetrick, J. Osborn, R. Sugar, D. Toussaint, M. Di Pierro, A. El-Khadra, A. S. Kronfeld, P. B. Mackenzie, D. Menscher, J. Simone. 2003-04-07. High-Precision Lattice QCD Confronts Experiment. https://doi.org/10.1103/physrevlett.92.022001

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