Systematics of the Reaction Between 10.3 and 19.0 MeV

摘要

The breakup reaction has been investigated in the past at several tandem accelerator energies below 20 MeV in a number of “classical” kinematical configurations. These data are compared with predictions of four modern high-precision nucleon-nucleon potentials, calculated for 2H(n,np)n, i.e., without inclusion of the Coulomb interaction. The results show a remarkably good agreement between data and theory in some situations such as the final-state interaction, indicating the smallness of three-nucleon-force effects as well as the insignificance of the Coulomb force for this particular configuration. Other configurations such as the symmetric space-star or quasi-free scattering are not well described. The discrepancies cannot be removed by including into three-nucleon Faddeev calculations the 2π-exchange Tucson-Melbourne three-nucleon force with the cutoff parameter adjusted individually for each nucleon-nucleon interaction to fit the experimental triton binding energy. In contrast to quasi-free or symmetric space-star scattering configurations a comparison with corresponding neutron-deuteron data shows that this discrepancy cannot be traced back to the missing Coulomb interaction.