Strong coupling constant and heavy quark masses in (2+1)-flavor QCD

摘要

We present a determination of the strong coupling constant and heavy quark masses in ( 2 + 1 )-flavor QCD using lattice calculations of the moments of the pseudoscalar quarkonium correlators at several values of the heavy valence quark mass with highly improved staggered quark action. We determine the strong coupling constant in the MS ˉ scheme at four low-energy scales corresponding to m c , 1.5 m c , 2 m c , and 3 m c , with m c being the charm quark mass. The novel feature of our analysis that up to 11 lattice spacings are used in the continuum extrapolations, with the smallest lattice spacing being 0.025?fm. We obtain Λ MS ˉ n f = 3 = 298 ± 16 ? ? MeV , which is equivalent to α s ( μ = M Z , n f = 5 ) = 0.1159 ( 12 ) . For the charm and bottom quark masses in the MS ˉ scheme, we obtain m c ( μ = m c , n f = 4 ) = 1.265 ( 10 ) ? ? GeV and m b ( μ = m b , n f = 5 ) = 4.188 ( 37 ) ? ? GeV .