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arXiv · hep-lat/0208038

$B^0-\bar{B}^0$ mixing in quenched lattice QCD

JLQCD Collaboration·S. Aoki·M. Fukugita·S. Hashimoto·K-I. Ishikawa·N. Ishizuka·Y. Iwasaki·K. Kanaya·T. Kaneko·Y. Kuramashi·M. Okawa·T. Onogi·N. Tsutsui·A. Ukawa·N. Yamada·T. Yoshie
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Abstract

We present our results of lattice calculations of $B$ parameters, which parameterize $ΔB$=2 transition amplitudes together with the leptonic decay constant. Calculations are made in the quenched approximation at $β$=5.7, 5.9, 6.0 and 6.1, using NRQCD action for heavy quark and the $O(a)$-improved Wilson action for light quark. The operators are perturbatively renormalized including the correction of $O(α_s/(aM)^m)$ ($m\ge$0). We examine the scaling behavior of $B$ parameters, and discuss the systematic uncertainties based on the results with several different truncations of higher order terms in 1/M and $α_s$ expansions. We find $B_{B_d}(m_b)=0.84(3)(5)$, $B_{B_s}/B_{B_d}=1.020(21)(^{+15}_{-16})(^{+5}_{-0})$ and $B_{S_s}(m_b)=0.85(1)(5)(^{+1}_{-0})$ in the quenched approximation. The errors represent statistical and systematic as well as the uncertainty in the determination of strange quark mass.

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JLQCD Collaboration, S. Aoki, M. Fukugita, S. Hashimoto, K-I. Ishikawa, N. Ishizuka, Y. Iwasaki, K. Kanaya, T. Kaneko, Y. Kuramashi, M. Okawa, T. Onogi, N. Tsutsui, A. Ukawa, N. Yamada, T. Yoshie. 2002-11-28. $B^0-\bar{B}^0$ mixing in quenched lattice QCD. https://doi.org/10.1103/physrevd.67.014506

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