CONICET | Buscador de Institutos y Recursos Humanos

The disappearance searching experiments nu_mu ---> nu_x use charged current quasielastic (CCQE) reaction to detect an arriving neutrino and reconstruct its energy, while the CC1 pi^+ production can mimic the CCQE signal process. In nu_mu --->nu_e appearance experiments, the NC1 pi^0 production process can lead to a fake e^- event by the impossibility for the detector of distinguish an arriving electron or a photon. Here we present a consistent model, from the point of view of the construction of the elemental amplitude, for the mentioned pion production background processes including bounding, smearing and final state interaction (FSI) effects in a single fashion. Results are comparable with more evolved approaches based on Monte Carlo simulations.