2009/01/31 by Karol Kampf, B. Moussallam, Bachir Moussallam · 90 citations
Mathematics · Physics and Astronomy · #Amplitude #Consistency (knowledge bases) #Coupling (piping) #Discrete mathematics #Flavour #High-Energy Particle Collisions Research #Lattice (music) #Logarithm #Mathematical analysis #Mathematical physics #Mathematics #Order (exchange) #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum mechanics #hep-ph
paper · pdf · doi:10.1103/physrevd.79.076005
published in Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields 79(7) (American Physical Society) · 20 pages, 1 figure; v2: comments and references added, accepted for publication in PRD
openalex publication_date 2009/04/14 · arxiv created 2009/05/05 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The corrections induced by light quark masses to the current algebra result for the \ensuremathπ0 lifetime are reexamined. We consider next-to-next-to-leading order corrections and we compute all the one-loop and the two-loop diagrams which contribute to the decay amplitude at this order in the two-flavor chiral expansion. We show that the result is renormalizable, as Weinberg consistency conditions are satisfied. We find that chiral logarithms are present at this order unlike the case at next-to-leading order. The result could be used in conjunction with lattice QCD simulations, the feasibility of which was recently demonstrated. We discuss the matching between the two-flavor and the three-flavor chiral expansions in the anomalous sector at order one-loop and derive the relations between the coupling constants. A modified chiral counting is proposed, in which ms counts as O(p). We have updated the various inputs needed and used this to make a phenomenological prediction.