2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/188342We discuss renormalization of propagator of interacting Rarita--Schwinger field. Spin-3/2 contribution after renormalization takes usual resonance form. For non-leading spin-1/2 terms we found procedure, which guarantees absence of poles in energy plane. The obtained renormalized propagator has one free parameter and is a straight generalization of the famous free propagator of Moldauer and Case. Application of this propagator for production of $Δ^{++}(1232)$ in $π^{+}\particle{p}\to π^{+}\particle{p}$ leads to good description of total cross-section and to reasonable agreement with results of partial wave analysis.19 pages, 3 figures, revtex4; misprints, min editorial changesHigh Energy Physics - PhenomenologyHigh Energy Physics - TheoryNuclear Theorytext