Determination of alpha(s) from the QCD static energy

作者：Bazavov Alexei^*; Brambilla Nora; Garcia i Tormo Xavier; Petreczky Peter; Soto Joan; Vairo Antonio

来源：Physical Review D - Particles, Fields, Gravitation and Cosmology, 2012, 86(11): 114031.

DOI：10.1103/PhysRevD.86.114031

We compare lattice data for the short-distance part of the static energy in 2 + 1 flavor quantum chromodynamics (QCD) with perturbative calculations, up to next-to-next-to-next-to leading-logarithmic accuracy. We show that perturbation theory describes very well the lattice data at short distances, and exploit this fact to obtain a determination of the product of the lattice scale r(0) with the QCD scale Lambda(MS) over bar. With the input of the value of r(0), this provides a determination of the strong coupling alpha(s) at the typical distance scale of the lattice data. We obtain alpha(s)(1.5 GeV) = 0.326 +/- 0.019, which provides a novel determination of alpha(s) with three-loop accuracy (including resummation of the leading ultrasoft logarithms), and constitutes one of the few low-energy determinations of alpha(s) available. When this value is evolved to the Z-mass scale M-Z, it corresponds to alpha(s)(M-Z) = 0.1156(-0.0022)(+0.0021). DOI: 10.1103/PhysRevD.86.114031

• 出版日期2012-12-20