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Semileptonic B Decays with Nf=2+1 Dynamical Quarks

J. Shigemitsu·C. T. H. Davies·A. Dougall·K. Foley·E. Gamiz·A. Gray·E. Gulez·G. P. Lepage·M. Wingate
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Abstract

Semileptonic, B --> pi l,nu, decays are studied on the MILC dynamical configurations using NRQCD heavy and Asqtad light quarks. We work with light valence quark masses ranging between m_s and m_s/8. Preliminary simple linear chiral extrapolations have been carried out for form factors f_para and f_perp at fixed E_pi. The chirally extrapolated results for the form factors f_+(q^2) and f_0(q^2) are then fit to the Becirevic-Kaidalov (BK) ansatz. Preliminary estimates of the CKM matrix element |V_{ub}| are presented based on the recently published branching fractions for B exclusive semileptonic decays by the CLEO collaboration.

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BibTeXRIS

J. Shigemitsu, C. T. H. Davies, A. Dougall, K. Foley, E. Gamiz, A. Gray, E. Gulez, G. P. Lepage, M. Wingate. 2004-08-11. Semileptonic B Decays with Nf=2+1 Dynamical Quarks. https://doi.org/10.1016/j.nuclphysbps.2004.11.123

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