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arXiv · hep-ph/0405039

eta, eta-prime -> pi^+ pi^- gamma with coupled channels

B. Borasoy·R. Nissler
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Abstract

The decays eta, eta-prime -> pi^+ pi^- gamma are investigated within an approach that combines one-loop chiral perturbation theory with a coupled channel Bethe-Salpeter equation which satisfies unitarity constraints and generates vector mesons dynamically from composite states of two pseudoscalar mesons. It is furthermore shown that the inclusion of the eta-prime as a dynamical degree of freedom does not renormalize the Wess-Zumino-Witten term.

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B. Borasoy, R. Nissler. 2004-05-05. eta, eta-prime -> pi^+ pi^- gamma with coupled channels. https://doi.org/10.1016/j.nuclphysa.2004.05.006

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