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arXiv · 0802.0873

Subleading Shape-Function Effects and the Extraction of |V_ub|

Keith S. M. Lee
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Abstract

We derive a class of formulae relating moments of B -> Xu l nu to B -> Xs gamma in the shape function region, where m_X^2 ~ m_b Lambda_QCD. We also derive an analogous class of formulae involving the decay B -> Xs l+ l-. These results incorporate Lambda_QCD/m_b power corrections, but are independent of leading and subleading hadronic shape functions. Consequently, they enable one to determine |V_ub|/|V_tb V_ts*| to subleading order in a model-independent way.

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Keith S. M. Lee. 2008-12-16. Subleading Shape-Function Effects and the Extraction of |V_ub|. https://doi.org/10.1103/physrevd.78.013002

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