2006/01/28 by U. Aglietti
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.nuclphysbps.2006.03.019
LaTeX file, 6 pages, no figures. To appear in the Proceedings of the 7th International Symposium on Radiative Corrections (application of quantum field theory to phenomenology) Shonan Village, Japan October 2-7, 2005 (Nucl. Phys. B Proc. Suppl.)
arxiv created 2006/01/28 · openalex publication_date 2006/04/23 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We show that most spectra in the semileptonic decay B -> Xu + l + nu, such as for example the distribution in the light-cone momentum p+ = EX - pX recently considered, do not have the same long-distance structure of the photon spectrum in the radiative decay B -> Xs + gamma. On the contrary, the semileptonic distribution in the final hadron energy EX is connected to the radiative spectrum via short-distance factors only. The EX distribution also has a specific infrared structure known as the ``Sudakov shoulder''. We also discuss an explicit check of the resummation formula for the semileptonic decays, based on a recent second-order computation.