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Complementary Observables for the Determination of |Vub| in Inclusive Semileptonic B Decays

Robert V. Kowalewski·Sven Menke
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Abstract

The determination of |Vub| from inclusive semileptonic B decays is limited by uncertainties in modelling the decay distributions in b->ulnu transitions. The largest uncertainties arise from the limited knowledge of the appropriate b quark mass and Fermi momentum to use in the parameterization of the shape function. This paper presents a new method in which these shape function parameters are constrained by the same data used to measure |Vub|. The method requires measurements of the momenta of both the charged lepton and the neutrino in semileptonic B decays. From these quantities two complementary observables can be constructed, one for discriminating between b->ulnu transitions and background and the other for constraining the shape function. Using this technique the uncertainties in |Vub| from the shape function may be significantly reduced.

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Robert V. Kowalewski, Sven Menke. 2002-06-24. Complementary Observables for the Determination of |Vub| in Inclusive Semileptonic B Decays. https://doi.org/10.1016/s0370-2693(02)02181-0

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