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arXiv · hep-ph/0409115

Subleading Shape Functions in Inclusive B Decays

Stefan W. Bosch·Matthias Neubert·Gil Paz
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Abstract

The contributions of subleading shape functions to inclusive decay distributions of B mesons are derived from a systematic two-step matching of QCD current correlators onto soft-collinear and heavy-quark effective theory. At tree-level, the results can be expressed in terms of forward matrix elements of bi-local light-cone operators. Four-quark operators, which arise at O(g^2), are included. Their effects can be absorbed entirely into a redefinition of other shape functions. Our results are in disagreement with some previous studies of subleading shape-function effects in the literature. A numerical analysis of B->X_u+l+nu decay distributions suggests that power corrections are small, with the possible exception of the endpoint region of the charged-lepton energy spectrum.

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Stefan W. Bosch, Matthias Neubert, Gil Paz. 2004-12-21. Subleading Shape Functions in Inclusive B Decays. https://doi.org/10.1088/1126-6708%2F2004%2F11%2F073

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