No abstract

The analyzing power A y (θ ) for neutron elastic scattering from 12 C has been measured for 33 neutron energies between E n = 2.2 and 8.5 MeV in the angular range from 25 • to 145 • in the laboratory system. The primary motivation for these measurements is the need for an accurate knowledge of A y (θ) for 12 C(n, n) 12 C elastic scattering to enable corrections to high-precision neutron-proton and neutron-deuteron A y (θ) data in the neutronenergy range below E n = 30 MeV. In their own right, 12 C(n, n) 12 C A y (θ) data are of crucial importance for improving both the parametrization of n-12 C scattering and our knowledge of the level scheme of 13 C. The present A y (θ ) data are compared with published data and previous phase-shift-analysis results.

LWThe neutron-neutron and neutron-proton 'SO scattering lengths a , and 4rp, reepectively, were determined simultaneously from the neutron-deuteron breakup reaction. Their comparison with the recommended valuea obtained from "two-bodyw reactionti gives a measure of the importance of three-nucleon force effects in the three-nucleon continuum. In order to check on the reuult obtained for u,,,, from the "two-body" x'-d capture reaction, a new measurement was performed at LANL. Pmlimiiary results of the three experiments are given.