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arXiv · hep-ph/0205039

Reducing theoretical uncertainties in mb and lambda1

Christian W. Bauer·Michael Trott
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Abstract

We calculate general moments of the lepton energy spectrum in inclusive semileptonic B -> X_c l νdecay. Moments which allow the determination of mb^{1S} and lambda1 with theoretical uncertainties Delta(mb^{1S}) ~ 0.04 GeV and Delta(lambda1) ~ 0.05 GeV^2 are presented. The short distance 1S mass is used to extract a mass parameter free of renormalon ambiguities. Moments which are insensitive to mb and lambda1 and therefore test the size of the 1/mb^3 matrix elements and the validity of the OPE are also presented. Finally, we give an expression for the total branching ratio with a lower cut on the lepton energy, which allows one to eliminate a source of model dependence in current determinations of |Vcb| from B -> X_c l νdecay.

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Christian W. Bauer, Michael Trott. 2002-05-06. Reducing theoretical uncertainties in mb and lambda1. https://doi.org/10.1103/physrevd.67.014021

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