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arXiv · hep-lat/0010089

B^0-\bar{B}^0 mixing with quenched lattice NRQCD

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

We present our recent results for the B-parameters, which parameterize the ΔB=2 transition amplitudes. Calculations are made in quenched QCD at β=5.7, 5.9, and 6.1, using NRQCD for heavy quark and the $O(a)$-improved action for light quark. The operators are perturbatively renormalized including corrections of O(α_s/am_Q). We examine scaling behavior of the B-parameters in detail, and discuss the systematic uncertainties using scatter of results with different analysis procedures adopted. As a result, we find B_{B_d}(m_b)=0.84(2)(8), B_{B_s}/B_{B_d}=1.017(10)(^{+4}_{-0}) and B_{S_s}(m_b)=0.87(1)(9)(^{+1}_{-0}) in the quenched approximation.

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JLQCD Collaboration, N. Yamada, S. Aoki, R. Burkhalter, M. Fukugita, S. Hashimoto, K-I. Ishikawa, N. Ishizuka, Y. Iwasaki, K. Kanaya, T. Kaneko, Y. Kuramashi, M. Okawa, T. Onogi, S. Tominaga, N. Tsutsui, A. Ukawa, T. Yoshié. 2000-11-04. B^0-\bar{B}^0 mixing with quenched lattice NRQCD. https://doi.org/10.1016/s0920-5632(01)00980-x

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