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Decay Constants of B and D Mesons from Non-perturbatively Improved Lattice QCD

K. C. Bowler·L. Del Debbio·J. M. Flynn·G. N. Lacagnina·V. I. Lesk·C. M. Maynard·D. G. Richards
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Abstract

The decay constants of B, D and K mesons are computed in quenched lattice QCD at two different values of the coupling. The action and operators are O(a) improved with non-perturbative coefficients. The results are f_B=195(6)(+24/-23) MeV, f_D=206(4)(+17/-10) MeV, f_B_s=220(6)(+23/-28) MeV, f_D_s=229(3)(+23/-12) MeV and f_K= 150(3)(+12/-8) MeV. Systematic errors are discussed in detail. Results for vector decay constants, flavour symmetry breaking ratios of decay constants, the pseudoscalar-vector mass splitting and D meson masses are also presented.

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K. C. Bowler, L. Del Debbio, J. M. Flynn, G. N. Lacagnina, V. I. Lesk, C. M. Maynard, D. G. Richards. 2001-10-10. Decay Constants of B and D Mesons from Non-perturbatively Improved Lattice QCD. https://doi.org/10.1016/s0550-3213(01)00511-9

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