Implications of a new effective chiral meson Lagrangian Original Research Article

Based on a recently derived effective chiral meson Lagrangian from the extended SU(2)⊗SU(2) Nambu–Jona-Lasinio (ENJL) model, in the linear realization of chiral symmetry, we extract to leading order in the 1/Nc expansion all associated relevant three-point functions ρ→ππ, σ→ππ, a1→ρπ, a1→σπ, as well as the amplitude for ππ scattering. We discuss the formal differences of these amplitudes as compared with those derived in the literature and calculate the associated decay widths and scattering parameters. The differences have two origins: