Impact of Four-Quark Shape Functions on Inclusive B Decay Spectra
High Energy Physics - Phenomenology
2009-01-07 v2
Abstract
It has recently been pointed out that a new class of subleading shape functions involving B-meson matrix elements of non-local four-quark operators contributes at order Lambda_{QCD}/m_b to B->X_u+l+nu decay distributions in the endpoint region. The corresponding functions f_u(omega) and f_v(omega) are estimated using the vacuum-insertion approximation. A numerical analysis of various B->X_u+l+nu decay spectra suggests that these power corrections are very small, below present theoretical uncertainties due to other subleading shape-function contributions.
Cite
@article{arxiv.hep-ph/0411027,
title = {Impact of Four-Quark Shape Functions on Inclusive B Decay Spectra},
author = {Matthias Neubert},
journal= {arXiv preprint arXiv:hep-ph/0411027},
year = {2009}
}
Comments
8 pages, 2 figures; minor revisions and figure added; version to appear in Eur. Phys. J. C