Processese+e−→ππ(π′)in the extended Nambu–Jona-Lasinio model

Abstract

The process e + e − → π + π − is described in the framework of the extended NJL model. Intermediate vector mesons ρ 0 (770), ω(782) and ρ ′ (1450) are taken into account. Our results are in satisfactory agreement with experimental data. The prediction for the process e + e − → ππ ′ (1300) is given. Here the main contribution is given by the diagram with intermediate ρ ′ (1450) meson.

A general framework to diagonalize vector–scalar and axial-vector–pseudoscalar transitions in the effective meson Lagrangian

“…The model describes both phases and gives a solid framework for the study of the transformation laws of the qq The source of interest regarding the chiral transformations of spin-1 fields resides in the use of these fields in the effective Lagrangians describing the strong interactions of hadrons at energies of ∼ 1 GeV [23,24,27]. Presently these theories are actively used in studies of τ -lepton decay modes [28], e + e − hadron production [29], and the QCD phase diagram [30,31]. The chiral transformations we suggest allow for greater freedom in the construction of such Lagrangians by noting that one may use different representations for these transformations as long as they obey the same group structure.…”