Subleading Shape Functions in Inclusive B Decays
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.
Cite
@article{arxiv.hep-ph/0409115,
title = {Subleading Shape Functions in Inclusive B Decays},
author = {Stefan W. Bosch and Matthias Neubert and Gil Paz},
journal= {arXiv preprint arXiv:hep-ph/0409115},
year = {2010}
}
Comments
22 pages, 2 figures; several typos corrected; version published in JHEP