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The determination of alpha_s from lattice QCD with 2+1 flavors of dynamical quarks

C. Davies·A. Gray·M. Alford·E. Follana·J. Hein·P. Lepage·Q. Mason·M. Nobes·J. Shigemit su·H. Trottier·M. Wingate
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Abstract

We describe the first lattice determination of the strong coupling constant with 3 flavors of dynamical quarks. The method follows previous analyses in using a perturbative expansion for the plaquette and Upsilon spectroscopy to set the scale. Using dynamical configurations from the MILC collaboration with 2+1 flavors of dynamical quarks we are able to avoid previous problems of having to extrapolate to 3 light flavors from 0 and 2. Our results agree with our previous work: alpha_s_MSbar(M_Z) = 0.121(3).

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C. Davies, A. Gray, M. Alford, E. Follana, J. Hein, P. Lepage, Q. Mason, M. Nobes, J. Shigemit su, H. Trottier, M. Wingate. 2002-09-13. The determination of alpha_s from lattice QCD with 2+1 flavors of dynamical quarks. https://doi.org/10.1016/s0920-5632(03)01631-1

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