Effects of the Pauli Principle on the Double Dalitz Decay of Pseudoscalar Mesons

Abstract

The differential decay rate for the double Dalitz decay ${\ensuremath{\pi}}^{0}\ensuremath{\rightarrow}{e}^{+}{e}^{\ensuremath{-}}{e}^{+}{e}^{\ensuremath{-}}$ is calculated exactly as a function of the virtual photon masses, with arbitrary form factors at the ${\ensuremath{\pi}}^{0}\ensuremath{\rightarrow}2\ensuremath{\gamma}$ vertex. The result is compared with the result of an approximate calculation using only a single Feynman diagram.