2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/193928Analysis of the $nd\to p(nn)$ reaction in a GeV-energy region is performed in the framework based on the multiple-scattering theory for the few-nucleon system. The special kinematic condition, when momentum transfer from neutron beam to final proton closes to zero, is considered. The possibility to extract the spin-dependent term of the elementary $np\to pn $ amplitude from $nd$-breakup process is investigated. The energy dependence of the ratio $R=\frac{dσ_{nd}} {dΩ} / \frac{dσ_{np}}{dΩ}$ is obtained taking account of the final-state interaction of the two outgoing neutrons in $^1 S_0$-state.to be published in Phys.Atom.NuclNuclear Theorytext