B meson decay constant from quenched Lattice QCD

JLQCD collaboration; S. Aoki; M. Fukugita; S. Hashimoto; N. Ishizuka; Y. Iwasaki; K. Kanaya; Y. Kuramashi; M. Okawa; A. Ukawa; T. Yoshié

arXiv · hep-lat/9711041

B meson decay constant from quenched Lattice QCD

JLQCD collaboration·S. Aoki·M. Fukugita·S. Hashimoto·N. Ishizuka·Y. Iwasaki·K. Kanaya·Y. Kuramashi·M. Okawa·A. Ukawa·T. Yoshié

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Abstract

A lattice QCD calculation of the B meson decay constant is presented. In order to investigate the scaling violation associated with the heavy quark, parallel simulations are carried out employing both Wilson and the O(a)-improved clover actions for the heavy quark. The discretization errors due to the large $b$ quark mass are estimated in a systematic way with the aid of the non-relativistic interpretation approach of El-Khadra, Kronfeld and Mackenzie. As our best value from the quenched simulations at $β$=5.9, 6.1 and 6.3 we obtain $f_B$=163$\pm$16 MeV and $f_{B_s}$=175$\pm$18 MeV in the continuum limit where the error includes both statistical and systematic uncertainties.

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JLQCD collaboration, S. Aoki, M. Fukugita, S. Hashimoto, N. Ishizuka, Y. Iwasaki, K. Kanaya, Y. Kuramashi, M. Okawa, A. Ukawa, T. Yoshié. 1997-11-19. B meson decay constant from quenched Lattice QCD. https://arxiv.org/abs/hep-lat/9711041

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