One-pion-exchange three-nucleon force and the A(y) puzzle - art. no. 031001

We consider a new three-nucleon force generated by the exchange of one pion in the presence of a 2N correlation. The underlying irreducible diagram ha s been recently suggested by the authors as a possible candidate to explain the puzzle of the vector analyzing powers A(y) and iT(11) for nucleon-deut eron scattering. Herein, we have calculated the elastic neutron-deuteron di fferential cross section, A(y), iT(11), T-20, T-21, and T-22 below breakup threshold by accurately solving the Alt-Grassberger-Sandhas equations with realistic interactions. We have also studied how A(y) evolves below 30 MeV. The results indicate that this new 3NF diagram provides one possible addit ional contribution, with the correct spin-isospin structure, for the explan ation of the origin of this puzzle.