Improved analysis of B → πeν from QCD sum rules on the light-cone

Ball, P.; Zwicky, R.

Abstract

We present a new calculation of the Brightarrowpi form-factor f+, relevant for the measurement of |Vub| from semileptonic Brightarrowpi transitions, from QCD sum rules on the light-cone. The new element is the calculation of radiative corrections to next-to-leading twist-3 accuracy. We find that these contributions are factorizable at O(alphas), which lends additional support to the method of QCD sum rules on the light-cone. We obtain f+(0) = 0.26+/-0.06+/-0.05, where the first error accounts for the uncertainty in the input-parameters and the second is a guesstimate of the systematic uncertainty induced by the approximations inherent in the method. We also obtain a simple parametrization of the form-factor which is valid in the entire kinematical range of semileptonic decays and consistent with vector-meson dominance at large momentum-transfer.

Citation

Ball, P., & Zwicky, R. (2001). Improved analysis of B → πeν from QCD sum rules on the light-cone. Journal of High Energy Physics, 2001(10), https://doi.org/10.1088/1126-6708/2001/10/019

• Journal Article Type: Article
• Publication Date: Oct 1, 2001
• Deposit Date: May 7, 2008
• Publicly Available Date: May 7, 2008
• Journal: Journal of High Energy Physics
• Print ISSN: 1126-6708
• Electronic ISSN: 1029-8479
• Publisher: Scuola Internazionale Superiore di Studi Avanzati (SISSA)
• Peer Reviewed: Peer Reviewed
• Volume: 2001
• Issue: 10
• DOI: https://doi.org/10.1088/1126-6708/2001/10/019
• Keywords: Standard model, Weak decays, B-physics, Sum rules.
• Public URL: https://durham-repository.worktribe.com/output/1583881