Low-Energy Interactions of Mesons with Participation of the First Radially Excited States in U (3) × U (3) NJL Model.

The U (3) × U (3) chiral symmetric NJL model describing pseudoscalar, vector, and axial-vector mesons in both the ground state and first radially excited states is shortly presented in this review. In this model, it is possible to describe a large number of low-energy interactions of mesons, τ lepton decays into mesons, and processes of meson production in electron–positron annihilations in satisfactory agreement with the experiments. In describing a number of processes, it turned out to be necessary to take into account the interactions of mesons in the final state. [ABSTRACT FROM AUTHOR]