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arXiv · 0706.3027

Final state radiation and a possibility to test a pion-photon interaction model near two-pion threshold

G. Pancheri·O. Shekhovtsova·G. Venanzoni
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Abstract

Final state radiation in the process $e^+e^-\toπ^+π^-$ is considered for the cuts used in the analysis of KLOE data at large angles. By means of a Monte Carlo event generator FEVA, effects of non-pointlike behaviour of pions are estimated in the framework of Resonance Perturbation Theory. An additional complication related with the $ϕ$ meson intermediate state is taken into account and the corresponding contributions (the direct decay $ϕ\toπ^+π^-γ$ and the double resonance decay $ϕ\toρ^\pmπ^\mp\toπ^+π^-γ$) are added to FEVA. A method to test effects of non-pointlike behaviour of pions in a model-independent way is proposed.

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G. Pancheri, O. Shekhovtsova, G. Venanzoni. 2007-06-20. Final state radiation and a possibility to test a pion-photon interaction model near two-pion threshold. https://doi.org/10.1134/s1063776108030072

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