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arXiv · hep-lat/0110087

B meson B-parameters and the decay constant in two-flavor dynamical QCD

JLQCD Collaboration·N. Yamada·S. Aoki·R. Bulkhalter·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 a two-flavor dynamical QCD calculation of the B meson B parameters and decay constant. We use NRQCD for heavy quark and the nonperturbatively O(a)-improved Wilson action for light quark at $β$=5.2 on a $20^3\times 48$ lattice. We confirm that the sea quark effect increases the heavy-light decay constant, while estimate of its magnitude depends significantly on the fitting form in the chiral extrapolation. For the B parameters, on the other hand, we do not find a significant sea quark effect. The chiral extrapolation with logarithmic term is examined for both quantities and compared with the prediction of ChPT.

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JLQCD Collaboration, N. Yamada, S. Aoki, R. Bulkhalter, 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. 2001-10-15. B meson B-parameters and the decay constant in two-flavor dynamical QCD. https://doi.org/10.1016/s0920-5632(01)01726-1

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