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Scaling and Further Tests of Heavy Meson Decay Constant Determinations from Nonrelativistic QCD

S. Collins·C. T. H. Davies·J. Hein·G. P. Lepage·C. J. Morningstar·J. Shigemitsu·J. Sloan
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Abstract

We present results for the B_s meson decay constant f_{B_s} from simulations at three lattice spacings in the range a^{-1}=1.1 to 2.6 GeV using NRQCD heavy quarks and clover light quarks in the quenched approximation. We study scaling of this quantity and check the consistency between mesons decaying from rest and from a state with nonzero spatial momentum. The cancellation of power law contributions that arise in the NRQCD formulation of heavy-light currents is discussed. On the coarsest lattice the D_s meson decay constant f_{D_s} is calculated. Our best values for the decay constants are given by f_{B_s} = 187(4)(4)(11)(2)(7)(6) MeV and f_{D_s} = 223(6)(31)(38)(23)(9)(^{+3}_{-1}) MeV.

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S. Collins, C. T. H. Davies, J. Hein, G. P. Lepage, C. J. Morningstar, J. Shigemitsu, J. Sloan. 2000-12-14. Scaling and Further Tests of Heavy Meson Decay Constant Determinations from Nonrelativistic QCD. https://doi.org/10.1103/physrevd.63.034505

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