The efficiency of a separable expansion method proposed by Ernst, Shakin, and Thaler is examined in three-nucleon calculations. Separable approximations with increasing accuracy are constructed for the ${}_{}{}^1{}_{}{}^{}\mathrm{S}_0^{}{}_{}{}^{}$ and ${}_{}{}^3{}_{}{}^{}\mathrm{S}_1^{}{}_{}{}^{}$${\mathrm{-}}^3$${\mathrm{D}}_1$ partial waves of the Paris potential. With these models we compute the three-body bound state and observables of the nucleon-deuteron scattering. The stability of the three-nucleon results is investigated as a function of the number of terms in the separable representation. Convergence is observed already for a few terms retained.

• Received 16 June 1986

DOI:https://doi.org/10.1103/PhysRevC.34.1187