eta,eta '->pi(+)pi(-)gamma with coupled channels

摘要

The decays eta, eta' --> 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' as a dynamical degree of freedom does not renormalize the Wess-Zumino-Witten term. (C) 2004 Elsevier B.V. All rights reserved.