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Comparative analysis of non-perturbative effects in B -> X_u l anti-nu_l decays

B. A. Kniehl·G. Kramer·J. -F. Yang
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Abstract

In order to extract the Cabibbo-Kobayashi-Maskawa matrix element |V_{ub}| from B -> X_u l anti-nu_l decays, the overwhelming background from B -> X_c l anti-nu_l decays must be reduced by appropriate acceptance cuts. We study the non-perturbative effects due to the motion of the b quark inside the B meson on the phenomenologically relevant decay distributions of B -> X_u l anti-nu_l in the presence of such cuts in a comparative analysis based on shape functions and the parton model in the light-cone limit. Comparisons with recent data from the CLEO, BABAR, and BELLE collaborations favor the shape-function approach.

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B. A. Kniehl, G. Kramer, J. -F. Yang. 2007-03-22. Comparative analysis of non-perturbative effects in B -> X_u l anti-nu_l decays. https://doi.org/10.1103/physrevd.75.074023

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