2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/48646We consider an extended Nambu--Jona-Lasinio (NJL) model for the light meson sector of QCD where unphysical quark production thresholds are excluded by an infrared cut-off on the momentum integration within quark loop diagrams. This chiral quark model conserves the low energy theorems. The infrared cut-off is fixed selfconsistently by the dynamically generated quark mass (quark condensate). The masses and decay widths of the σ- and ρ-mesons are described in the model.LaTeX, 12 pages, 3 figures, 1 tableHigh Energy Physics - Phenomenologytext