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arXiv · 1011.2166

B -> D* l nu at zero recoil: an update

Jon A. Bailey·A. Bazavov·C. Bernard·C. M. Bouchard·C. DeTar·A. X. El-Khadra·E. D. Freeland·E. Gámiz·Steven Gottlieb·U. M. Heller·J. E. Hetrick·A. S. Kronfeld·J. Laiho·L. Levkova·P. B. Mackenzie·M. B. Oktay·J. N. Simone·R. Sugar·D. Toussaint·R. S. Van de Water
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Abstract

We present an update of our calculation of the form factor for B -> D* l nu at zero recoil, with higher statistics and finer lattices. As before, we use the Fermilab action for b and c quarks, the asqtad staggered action for light valence quarks, and the MILC ensembles for gluons and light quarks (Lüscher-Weisz married to 2+1 rooted staggered sea quarks). In this update, we have reduced the total uncertainty on F(1) from 2.6% to 1.7%. At Lattice2010 we presented a still-blinded result, but this writeup includes the unblinded result from the September 2010 CKM workshop.

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Jon A. Bailey, A. Bazavov, C. Bernard, C. M. Bouchard, C. DeTar, A. X. El-Khadra, E. D. Freeland, E. Gámiz, Steven Gottlieb, U. M. Heller, J. E. Hetrick, A. S. Kronfeld, J. Laiho, L. Levkova, P. B. Mackenzie, M. B. Oktay, J. N. Simone, R. Sugar, D. Toussaint, R. S. Van de Water. 2010-11-09. B -> D* l nu at zero recoil: an update. https://arxiv.org/abs/1011.2166

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