Properties of<i>B</i>mesons in lattice QCD

Abstract

The results of an extensive study of B-meson properties in quenched lattice QCD are presented. The studies are carried out in the static quark limit where the b quark is taken to be infinitely massive. Our computations rely on a multistate smearing method introduced previously, with smearing functions generated from a relativistic lattice quark model. Systematic errors arising from excited state contamination, finite volume effects, and the chiral extrapolation for the light quarks are estimated. We obtain continuum results for the mass splitting ${\mathit{M}}_{\mathit{B}\mathit{s}}$-${\mathit{M}}_{\mathit{B}\mathit{u}}$=86\ifmmode\pm\else\textpm\fi{}12(stat${)}_{\mathrm{\ensuremath{-}}9}^{+7}$(syst) MeV, the ratio of decay constants ${\mathit{f}}_{\mathit{B}\mathit{s}}$/${\mathit{f}}_{\mathit{B}\mathit{u}}$=1.22\ifmmode\pm\else\textpm\fi{}0.04(stat)\ifmmode\pm\else\textpm\fi{}0.02(syst). For the B-meson decay constant we separately exhibit the sizable uncertainties in the extrapolation to the continuum limit (a\ensuremath{\rightarrow}0) and higher-order perturbative matching. We obtain ${\mathit{f}}_{\mathit{B}}$=188\ifmmode\pm\else\textpm\fi{}23(stat)\ifmmode\pm\else\textpm\fi{}15(syst${)}_{\mathrm{\ensuremath{-}}0}^{+26}$(extrap)\ifmmode\pm\else\textpm\fi{}14(pert) MeV.