Two-photon decays of pi^0, eta and eta-prime

Abstract

We investigate the decays of pi^0, eta and eta-prime into two photons in an effective U(3) chiral Lagrangian approach without employing large N_c arguments. Tree level and one-loop contributions from the anomalous Wess-Zumino-Witten Lagrangian are calculated and the importance of eta--eta-prime mixing is discussed. Unitarity corrections beyond one-loop play an important role for the decays with off-shell photons and are included by employing a coupled channel Bethe-Salpeter equation which satisfies unitarity constraints and generates vector-mesons from composed states of two pseudoscalar mesons.

27 pages, 10 figures

References in corpus (4)

• Odd-intrinsic-parity processes within the Resonance Effective Theory of QCD
• Pion distribution amplitudes within the instanton model of QCD vacuum
• Hadronic decays of eta and eta-prime with coupled channels
• S-wave Meson-Meson Scattering from Unitarized U(3) Chiral Lagrangians

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• Electromagnetic axial anomaly in a generalized linear sigma model
• Triality selection rules of Octonion and Quantum Mechanics
• Can one see the number of colors in eta, eta-prime --> pi^+ pi^- gamma?