2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/82270We show that the Q-box expansion of nuclear many-body physics can be applied in nuclear effective field theory with explicit pions and external sources. We establish the corresponding power counting and give an algorithm for the construction of a hermitean and energy-independent potential for arbitrary scattering processes on nucleons and nuclei to a given order in the chiral expansion. Various examples are discussed in some detail.22 pp, 12 figsNuclear Theorytext