Few nucleon experiments with fast polarized neutrons

Abstract

Few-nucleon problems are studied at the polarized neutron facility of the Karlsruhe cyclotron in scattering experiments on very light nuclei. In a first series of experiments the analyzing power A_y( ) of the elastic scattering of neutron on H, ²H, ³He, and ⁴He has been measured in the energy range up to 50 MeV. These data have been analyzed and corrected for multiple scattering and finite geometry effects. The agreement with existing data sets is good. However, the accuracy could be improved considerably in most cases. Present work is concentrated on detailed studies of the n-p system. Sensitivity calculations show the need for precise data for the backward angle differential cross section and for the spin correlation parameter A_yy. Both experiments are in progress at present. A new phase shift analysis is being performed in the energy range from 15 to 50 MeV.