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arXiv · 0712.0466

Semileptonic B decays and the inclusive determination of |V(ub)|

P. Giordano
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Abstract

We present a new theoretical framework for the study of $B\to X_u \ell ν$ decays, which includes all known perturbative and non-perturbative contributions and a description of leading and subleading Fermi motion effects. The perturbative and non-perturbative regimes are separated by a ``hard'' Wilsonian cutoff $μ\sim 1$ GeV. We bring into focus some problems related to the high $q^2$ region and to Weak Annihilation effects. We provide estimates of the CKM parameter $|V_{ub}|$ using the described framework and discuss the related theoretical uncertainty.

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P. Giordano. 2007-12-04. Semileptonic B decays and the inclusive determination of |V(ub)|. https://doi.org/10.1088/1742-6596/110/5/052017

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