Pole extrapolation in the neutron-deuteron scattering system and the deuteron asymptotic normalizations

Differential cross sections and tensor polarizations of elastic neutron-deuteron scattering (n-d) are calculated at $E_{\mathrm{lab}}^{\mathrm{n}}<15\mathrm{}$ MeV with different nuclear potentials. The pole extrapolation of these model data reproduces the $S$-state normalization within 1% and misses the $D$- to $S$-state ratio $\eta$ by about 5%. Approximate Coulomb distortion corrections to n-d tensor polarization calculations that improve the agreement with proton-deuteron (p-d) data yield smaller contributions to $\eta$ than found previously within a distorted-wave Born approximation. Extrapolation of recent n-d differential cross section data and Coulomb corrected p-d tensor polarization leads to deuteron asymptotic normalizations compatible with current experimental values.