Resonances and weak interactions in $D^{+}\to {\pi }^{+}{\pi }^{-}{\pi }^{+}$ decays

Abstract

We describe the $\pi \pi$ $S$-wave in $D^{+}\to {\pi }^{+}{\pi }^{-}{\pi }^{+}$ decays using a unitary model for the $\pi \pi$ Final State Interactions (FSI). The three body decay is treated as a quasi two-body process where, at the weak vertex, the D meson decays into a resonance and a pion. The weak part of the decay amplitude is evaluated using the effective weak Hamiltonian within the factorization approximation.

Comments: 4 pages. Contribution to the X Hadron Physics, Florianopolis-Brazil, March 26-31, 2007