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arXiv · 0707.2493

Inclusive semileptonic B decays and the determination of |V_ub|

P. Gambino·P. Giordano·G. Ossola·N. Uraltsev
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Abstract

We study the triple differential distribution of B-> Xu l nu, consistently including all perturbative and non-perturbative effects through O(alphas^2 beta_0) and O(1/mb^3). The Fermi motion is parameterized in terms of a single light-cone function for each structure function and for any value of q^2, accounting for all subleading effects. We discuss the problems and uncertainties related to the high-q^2 tail and to Weak Annihilation effects. We work in the kinetic scheme, a framework characterized by a Wilsonian treatment with a hard cutoff mu ~ 1GeV. Our method is illustrated with the extraction of |V_ub| from some of the latest experimental data, providing a detailed estimate of the theoretical uncertainty.

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P. Gambino, P. Giordano, G. Ossola, N. Uraltsev. 2007-10-18. Inclusive semileptonic B decays and the determination of |V_ub|. https://doi.org/10.1088/1126-6708%2F2007%2F10%2F058

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