2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/41726Given the most general Lorentz invariant four-fermion effective interaction possible for two neutrinos and two charged fermions, whether quarks or leptons, all possible 2-to-2 processes involving two neutrinos, whether Dirac or Majorana ones, and two charged fermions are considered. Explicit and convenient expressions are given for the associated differential cross-sections. Such a parametrization should help assess the sensitivity to physics beyond the Standard Model of neutrino beam experiments which are in the design stage at neutrino factories.To be published in the Proceedings of the Second International Workshop on Contemporary Problems in Mathematical Physics, Cotonou, Republic of Benin, 15 pagesHigh Energy Physics - Phenomenologytext