2005/02/12 by Patricia Ball, Angelique N. Talbot, Angelique Talbot · 6 citations
Physics and Astronomy · #Amplitude #Conformal map #Distribution (mathematics) #Factorization #Geometry #Hadron #High-Energy Particle Collisions Research #Light cone #Meson #Observable #Order (exchange) #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum mechanics #Twist #hep-ph
paper · pdf · doi:10.1088/1126-6708/2005/06/063
published as JHEP0506:063,2005 · 19 pages, 10 figures
arxiv created 2005/02/12 · openalex publication_date 2005/06/24 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Leading-twist distribution amplitudes (DAs) of light mesons like pi,rho etc. describe the leading nonperturbative hadronic contributions to exclusive QCD reactions at large energy transfer, for instance electromagnetic form factors. They also enter B decay amplitudes described in QCD factorisation, in particular nonleptonic two-body decays. Being nonperturbative quantities, DAs cannot be calculated from first principles, but have to be described by models. Most models for DAs rely on a fixed order conformal expansion, which is strictly valid for large factorisation scales, but not always sufficient in phenomenological applications. We derive models for DAs that are valid to all orders in the conformal expansion and characterised by a small number of parameters which are related to experimental observables.