Stapp parameterization and scattering phases for coupled states

Variable phase approach is viewed for two-channel scattering. The search of the scattering phases and mixing parameter for coupled states 3S1–3D1 using Stapp parameterization is carried out. The nucleon-nucleon potential in the coordinate representation is used for numerical calculations. The influence of the choice of a numerical method (method Euler and methods Runge-Kutta) on the calculations of scattering phases and the mixing parameter is taken into account.