Possible three-nucleon force effects in D-P scattering at low energies
  We present measurements of the analyzing powers Ay and iT11 for proton-deuteron scattering at Ecm=432 keV. Calculations using a realistic nucleon-nucleon potential (Argonne V18) are found to underpredict both analyzing powers by 40. The inclusion of the Urbana three-nucleon interaction does not significantly modify the calculated analyzing powers. Due to its short range, it is difficult for this three-nucleon interaction to affect Ay and iT11 at this low energy. The origin of the discrepancy remains an open question. 
C. R. Brune, W. H. Geist, H. J. Karwowski, E. J. Ludwig, K. D. Veal,   M. H. Wood, A. Kievsky, S. Rosati and M. Viviani