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Electromagnetic Transition Form Factors of Light Mesons

P. Maris·P. C. Tandy
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Abstract

We study selected meson transition processes and associated form factors within a model of QCD based on the Dyson--Schwinger equations truncated to ladder-rainbow level. The infrared structure of the ladder-rainbow kernel is described by two parameters; the ultraviolet behavior is fixed by the one-loop renormalization group behavior of QCD. The work is restricted to the u and d quark sector and allows a Poincare'-covariant study of the radiative decays: rho -> pi + gamma, omega -> pi + gamma, and pi^0 -> gamma + gamma. Particular attention is paid to the form factors for the associated transitions: gamma^* + pi^0 -> gamma, gamma^* + pi^0 -> gamma^*, gamma^* + pi -> rho and gamma^* + rho -> pi. The latter two processes are of interest as contributors to meson electroproduction from hadronic targets away from the s-channel resonance region. We use the present QCD model to explore limitations to the assumption that coupling to a t-channel virtual qbar-q correlation can be modeled as meson exchange.

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P. Maris, P. C. Tandy. 2002-01-08. Electromagnetic Transition Form Factors of Light Mesons. https://doi.org/10.1103/physrevc.65.045211

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