ΛdScattering as a Probe of theΛNCore Potential

Nonlocal separable (NLS), $S$-wave, spin-dependent, central potentials and a Faddeev formalism are used to solve the $\Lambda d$ scattering problem. The $\mathrm{NN}$ interaction is represented by an attractive NLS potential. Each of the $\Lambda N$ interactions is represented by the sum of an attractive and a repulsive (core) NLS potential. Three different forms are used for this core potential, including no core at all. For a given $\Lambda N$ spin each $\Lambda N$ potential is adjusted to give the same low-energy scattering parameters, and the potentials with a core are adjusted to give the same phase shift over a wide energy range, as that given by a phenomenological local potential with a hard core. The $\Lambda N$ wave functions and off-shell transition matrices are compared to see how each reflects the presence of the $\Lambda N$ core potential. For incident $\Lambda$ laboratory momentum in the range 100-300 $\frac{\mathrm{MeV}}{c}$ the $\Lambda d$ cross sections are reduced by (13-25)%, and they do depend on the off-shell behavior of the $\Lambda N$ amplitude.