TY - JOUR AU - Spitz, A. AU - Hoeber, H. AU - Eicker, N. AU - Güsken, S. AU - Lippert, Th. AU - Schilling, K. AU - Struckmann, T. AU - Ueberholz, P. AU - Viehoff, J. TI - α S from Υ spectroscopy with dynamical Wilson fermions JO - Physical review / D VL - 60 IS - 7 SN - 0556-2821 CY - Melville, NY PB - Inst.812068 M1 - FZJ-2019-01094 SP - 074502 PY - 1999 AB - We estimate the QCD coupling constant from a lattice calculation of the bottomonium spectrum. The second order perturbative expansion of the plaquette expectation value is employed to determine αS at a scale set by the 2S−1S and 1P−1S level splittings. The latter are computed in NRQCD in a dynamical gauge field background with two degenerate flavors of Wilson quarks at intermediate masses and extrapolated to the chiral limit. Combining the Nf=2 result with the quenched result at equal lattice spacing we extrapolate to the physical number of light flavors to find a value of α(5)¯MS(mZ)=0.1118(17). The error quoted covers both statistical and systematic uncertainties in the scale determination. An additional 5% uncertainty comes from the choice of the underlying sea quark formulation and from truncation errors in perturbative expansions. LB - PUB:(DE-HGF)16 DO - DOI:10.1103/PhysRevD.60.074502 UR - https://juser.fz-juelich.de/record/860319 ER -