2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/82370The low energy $n-\nuc{3}{H}$ elastic cross sections near the resonance peak are calculated by solving the 4-nucleon problem with realistic NN interactions. Three different methods -- Alt, Grassberger and Shandas (AGS), Hyperspherical Harmonics and Faddeev-Yakubovsky -- have been used and their respective results are compared. We conclude on a failure of the existing NN forces to reproduce the $n-\nuc{3}{H}$ total cross section.To be published in Phys. Rev. CNuclear Theorytext