2009/12/08 by Piotr Kotko, Michał Praszałowicz, Michal Praszalowicz
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.81.034019
published as Phys.Rev.D81:034019,2010 · 38 pages, 9 figures. Refs. added
arxiv created 2009/12/08 · openalex publication_date 2010/02/16 · arxiv updated 2010/06/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Photon distribution amplitudes up to twist four are calculated within the nonlocal chiral quark model with a simple pole ansatz for momentum dependence of the constituent quark mass. Calculations are performed using a modified electromagnetic vector current in order to satisfy Ward identities. Quark condensate and magnetic susceptibility of the QCD vacuum entering definitions of the distribution amplitudes are computed and compared with existing phenomenological estimates. Both real and off-shell photons are considered and relevant form factors are calculated. Our results are analytical up to the numerical solution of certain algebraic equations.