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arXiv · hep-lat/9811003

Non-perturbatively Improved Heavy-Light Mesons: Masses and Decay Constants

D. Becirevic·Ph. Boucaud·J. P. Leroy·V. Lubicz·G. Martinelli·F. Mescia·F. Rapuano
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Abstract

We present a study of the heavy-light spectrum and of the D- and B-meson decay constants. The results wer e obtained in the quenched approximation, by using the non-perturbatively improved Clover lattice action at beta=6.2, with a sample of 100 configurations, on a 24^3 x 64 lattice. After a careful analysis of th e systematic errors present in the extraction of the physical results, by assuming quite conservative discretization errors, we find f_Ds=231 +/- 12^{+6}_{-1} MeV, f_D = 211 +/- 14^{+0}_{-12} MeV, f_Ds/f_D=1.10(2), f_Bs = 204 +/- 16^{+28}_{-0} MeV, f_B = 179 +/- 18^{+26}_{-9} MeV, f_Bs/f_B=1.14(3)^{+0}_{-1}. Our results, which have smaller discretization errors than many previous estimates at fixed value of the lattice spacing $a$, support a large value of f_B in the quenched approximation.

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D. Becirevic, Ph. Boucaud, J. P. Leroy, V. Lubicz, G. Martinelli, F. Mescia, F. Rapuano. 1998-11-02. Non-perturbatively Improved Heavy-Light Mesons: Masses and Decay Constants. https://doi.org/10.1103/physrevd.60.074501

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