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Ladder Dyson-Schwinger calculation of the anomalous gamma-3pi form factor

Stephen R. Cotanch·Pieter Maris
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Abstract

The anomalous processes, γ\to 3 πand γπ\to ππ, are investigated within the Dyson-Schwinger framework using the rainbow-ladder approximation. Calculations reveal that a complete set of ladder diagrams beyond the impulse approximation are necessary to reproduce the fundamental low-energy theorem for the anomalous form factor. Higher momentum calculations also agree with the limited form factor data and exhibit the same resonance behavior as the phenomenological vector meson dominance model.

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Stephen R. Cotanch, Pieter Maris. 2003-08-03. Ladder Dyson-Schwinger calculation of the anomalous gamma-3pi form factor. https://doi.org/10.1103/physrevd.68.036006

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