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Decay constants of charm and beauty pseudoscalar heavy-light mesons on fine lattices

A. Ali Khan·V. Braun·T. Burch·M Göckeler·G. Lacagnina·A. Schäfer·G. Schierholz
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Abstract

We compute decay constants of heavy-light mesons in quenched lattice QCD with a lattice spacing of a ~ 0.04 fm using non-perturbatively O(a) improved Wilson fermions and O(a) improved currents. We obtain f_{D_s} = 220(6)(5)(11) MeV, f_D = 206(6)(3)(22) MeV, f_{B_s} = 205(7)(26)(17) MeV and f_B = 190(8)(23)(25) MeV, using the Sommer parameter r_0 = 0.5 fm to set the scale. The first error is statistical, the second systematic and the third from assuming a +-10% uncertainty in the experimental value of r_0. A detailed discussion is given in the text. We also present results for the meson decay constants f_K and f_πand the ρmeson mass.

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A. Ali Khan, V. Braun, T. Burch, M Göckeler, G. Lacagnina, A. Schäfer, G. Schierholz. 2007-06-29. Decay constants of charm and beauty pseudoscalar heavy-light mesons on fine lattices. https://doi.org/10.1016/j.physletb.2007.06.066

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