1997/06/16 by Ulf-G. Meißner · 1 citation
Physics and Astronomy · #Hadron #High-Energy Particle Collisions Research #Isospin #Nuclear physics #Nucleon #Particle physics #Particle physics theoretical and experimental studies #Perturbative QCD #Physics #Pion #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum electrodynamics #Quantum mechanics #Scattering #Symmetry (geometry) #hep-ph #nucl-th
paper · pdf · doi:10.1016/s0375-9474(97)00668-4
published as Nucl.Phys. A629 (1998) 72c-81c · 10 pp, LaTeX file, 3 figures, uses espcrc1.sty and epsf, plenary talk, QULEN '97, Osaka, May 1997, to be published in the proceedings
arxiv created 1997/06/16 · openalex publication_date 1998/02/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
I discuss recent progress made in calculating electromagnetic corrections in the framework of the effective field theory of QCD. In the case of elastic pion-pion scattering, strong interaction predictions have been worked out to two loop accuracy. I present first results for the electromagnetic corrections in the case of neutral pions. Here, the only sizeable effect comes from the charged to neutral pion mass difference. In the presence of nucleons, isospin violation can be measured in threshold pion photoproduction. I review the present status of the theoretical predictions and the experimental data. I argue that a deeper understanding of isospin violation based on a more precise study of such reactions can be achieved.