Thee+e−→η(η′)2πprocess in the extended Nambu–Jona-Lasinio model

Abstract

Process of electron-positron annihilation into $\eta(\eta')2\pi$ is described within the extended NJL model in the energy range up to about 2 GeV. Contributions of intermediate vector mesons $\rho(770)$ and $\rho(1450)$ are taken into account. Results for the $\eta2\pi$ channel are found to be in a reasonable agreement with experimental data. Predictions for production of $\eta' 2\pi$ are given. The corresponding estimations for decays $\tau\to\eta(\eta')2\pi\nu$ are given in Appendix.