Low-energy scattering in four nucleon systems. Method of Cluster Reduction

A method using an expansion of the four-body Yakubovsky wave function components onto the basis of the Faddeev-equation solutions for the two-cluster sub-Hamiltonian eigenfunctions is exploited for computations of low-energy scattering parameters in four nucleon systems. Results of calculations of low-energy scattering parameters in $n-{^3}$H, $n-{^3}$He are presented.