Precise measurements of deuteron vector and tensor analyzing powers Ayd, Axx, Ayy, and Axz in d-p elastic scattering were performed via 1H(d→,d)p and 1H(d→,p)d reactions at three incoming deuteron energies of Edlab = 140, 200, and 270 MeV. A wide range of center-of-mass angles from ≈ 10° to 180° was covered. The cross section was measured at 140 and 270 MeV at the same angles. These high precision data were compared with theoretical predictions based on exact solutions of three-nucleon Faddeev equations and modern nucleon-nucleon potentials combined with three-nucleon forces. Three-body interactions representing a wide range of present day models have been used: the Tucson-Melbourne 2 π-exchange model, a modification thereof closer to chiral symmetry, the Urbana IX model, and a phenomenological spin-orbit ansatz. Large three-nucleon force effects are predicted, especially at the two higher energies. However, only some of them, predominantly dσ/dΩ and Ayd, are supported by the present data. For tensor analyzing powers the predicted effects are in drastic conflict to the data, indicating defects of the present day three-nucleon force models.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics