2005/05/10 by Sébastien Descotes–Genon, Bachir Moussallam, B. Moussallam +1
Mathematics · Physics and Astronomy · #Graph #High-Energy Particle Collisions Research #Lagrangian #Lepton #Matching (statistics) #Mathematical physics #Mathematics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum electrodynamics #Quantum mechanics #Radiative transfer #Renormalization #Theoretical physics #Vertex (graph theory) #hep-ph
paper · pdf · doi:10.1140/epjc/s2005-02316-8
published as Eur.Phys.J.C42:403-417,2005 · 28 pages, latex
arxiv created 2005/05/10 · openalex publication_date 2005/07/19 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We focus on the chiral Lagrangian couplings describing radiative corrections to weak semi-leptonic decays and relate them to the decay amplitude of a lepton, computed by Braaten and Li at one loop in the Standard Model. For this purpose, we follow a two-step procedure. A first matching, from the Standard Model to Fermi theory, yields a relevant set of counterterms. The latter are related to chiral couplings thanks to a second matching, from Fermi theory to the chiral Lagrangian, which is performed using the spurion method. We show that the chiral couplings of physical relevance obey integral representations in a closed form, expressed in terms of QCD chiral correlators and vertex functions. We deduce exact relations among the couplings, as well as numerical estimates which go beyond the usual log(M_Z/M_ρ) approximation.