2006/08/04 by U. Aglietti, Ugo Aglietti, Giancarlo Ferrera +1 · 4 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1016/j.nuclphysb.2007.01.014
published as Nucl.Phys.B768:85-115,2007 · 28 pages, 12 figures
arxiv created 2006/08/04 · openalex publication_date 2007/01/21 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/04
We compare experimental spectra of radiative and semileptonic B decays with the predictions of a model based on soft-gluon resummation to next-to-next-to leading order and on a ghost-less time-like coupling. We find a good agreement with photon spectra in the radiative decay and with hadron mass distributions in the semileptonic one: the extracted values for alphaS(mZ) are in agreement with the current PDG average within at most two standard deviations. The agreement is instead less good for the electron spectra measured by BaBar and Belle in semileptonic decays for small electron energies (< 2.2 GeV): our spectrum is harder. We also show that, in general, the inclusion of next-to-next-to-leading order effects is crucial for bringing the model closer to the data and that the non-power expansion introduced in the framework of analytic coupling studies does not accurately describe soft-gluon effects.