2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/190997We present a simple model for the $γN \to ππN$ reaction which reproduces the cross sections of the $π^+ π^- p, π^+ π^- n, π^+ π^0 n$ and $π^- π^0 p$ channels over the range of the energies 0.41-0.85 GeV. We use the dynamical model for the resonances, Δ(1232), N^*(1520) and ρ-meson. The total photoabsorption off a nucleon is also discussed.Revtex file, 25 pages, 8 figures, uses here.sty, psfig.styNuclear TheoryHigh Energy Physics - Phenomenologytext