First measurements of the analyzing powers of the proton-deuteron break-up reaction at large proton scattering angles

A measurement of the analyzing powers for the H-2((p) over right arrow ,pp)n break-up reaction was carried out at KVI exploiting a polarized-proton beam at 135 MeV. In this work, we extended the earlier measurements that were done for kinematical configurations at small proton scattering angles to large angles. The results are compared with theoretical calculations based on a two-nucleon (NN) potential alone or combined with a three-nucleon (3N) potential. The theoretical calculations describe the main features of the measured distributions, but none of them can reproduce the details. This indicates the need for further development of the 3N force models.