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arXiv · hep-lat/9809152

Scaling behavior of $f_{B}$ with NRQCD

JLQCD Collaboration·K-I. Ishikawa·N. Yamada·S. Aoki·M. Fukugita·S. Hashimoto·N. Ishizuka·Y. Iwasaki·K. Kanaya·T. Kaneda·S. Kaya·Y. Kuramashi·H. Matsufuru·M. Okawa·T. Onogi·S. Tominaga·N. Tsutsui·A. Ukawa·T. Yoshié
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Abstract

We investigate the scaling behavior of the $B$ meson decay constant $f_B$ and $f_{B_{s}}$ at $β$$=$$5.7, 5.9, 6.1$, employing the NRQCD heavy quark action and the clover light quark action. Mixing effect from dimension-4 operator in the heavy-light axial-vector current is studied, and we find that the $a$ dependence of $f_B$ is significantly reduced. Our preliminary result for the decay constants in the quenched approximation is $f_{B}$$=$$162(^{+35}_{-18})$ MeV, $f_{B_{s}}$$=$$190(^{+40}_{-19})$ MeV, and $f_{B_{s}}/f_{B}$$=$$1.18(^{+6}_{-6})$.

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JLQCD Collaboration, K-I. Ishikawa, N. Yamada, S. Aoki, M. Fukugita, S. Hashimoto, N. Ishizuka, Y. Iwasaki, K. Kanaya, T. Kaneda, S. Kaya, Y. Kuramashi, H. Matsufuru, M. Okawa, T. Onogi, S. Tominaga, N. Tsutsui, A. Ukawa, T. Yoshié. 1998-09-20. Scaling behavior of $f_{B}$ with NRQCD. https://doi.org/10.1016/s0920-5632(99)85074-9

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