The quark loop calculation of the gamma -> 3 pi form factor

Abstract

The presently experimentally interesting form factor for the anomalous process gamma -> pi^+ pi^0 pi^- is calculated as the quark "box"-amplitude where the intermediate fermion loop is the one of constituent quarks with the pseudoscalar coupling to pions. This also corresponds to the form factor, in the lowest order in pion interactions, of the sigma-model and of the chiral quark model. We give the analytic expression for the form factor in terms of an expansion in the pion momenta up to the order O(p^8) relative to the soft point result, and also perform its exact numerical evaluation. We compare our predictions with those of the vector meson dominance and chiral perturbation theory, as well as with the scarce data available so far.

revtex, 12 pages including 3 eps figures

Cited by in corpus (9)

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• Axial anomaly and the interplay of quark loops with pseudoscalar and vector mesons in the gamma* --> pi+ pi0 pi- process
• Photon-3-Pion And Pion-2-Photon Form Factors From Dynamical Constituent Quarks
• Phenomenological Schwinger-Dyson approach to eta-eta' mass matrix
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