2001/10/08 by Patricia Ball, Roman Zwicky · 5 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Parametrization (atmospheric modeling) #Particle physics theoretical and experimental studies #QCD sum rules #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Radiative transfer #Simple (philosophy) #Sum rule in quantum mechanics #hep-ph
paper · pdf · doi:10.1088/1126-6708/2001/10/019
published as JHEP 0110:019,2001 · 12 pages, 4 figures
arxiv created 2001/10/08 · openalex publication_date 2001/10/17 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present a new calculation of the B->pi form-factor f+, relevant for the measurement of |Vub| from semileptonic B->pi 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.