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Lattice measurement of the Isgur-Wise functions tau_1/2 and tau_3/2

D. Becirevic·B. Blossier·Ph. Boucaud·G. Herdoiza·J. P. Leroy·A. Le Yaouanc·V. Morenas·O. Pene
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Abstract

We propose a method to compute the Isgur-Wise form factors tau_1/2(1) and tau_3/2(1) for the decay of B mesons into orbitally excited (P wave) D** charmed mesons on the lattice in the static limit. We also present the result of an exploratory numerical simulation which shows that the signal/noise ratio allows for a more dedicated computation. We find tau_1/2(1)=0.38(5) and tau_3/2(1)= 0.53(8), with yet unknown systematic errors. These preliminary numbers agree fairly well with theoretical expectation.

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D. Becirevic, B. Blossier, Ph. Boucaud, G. Herdoiza, J. P. Leroy, A. Le Yaouanc, V. Morenas, O. Pene. 2004-06-18. Lattice measurement of the Isgur-Wise functions tau_1/2 and tau_3/2. https://doi.org/10.1016/j.physletb.2005.01.054

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