Analysing power in neutron-proton and neutron-deuteron scattering at 14 MeV

Abstract

Analysing power data in n-p and n-d elastic scattering at 14 MeV were deduced from asymmetry measurements using a polarized neutron beam arrangement consisting of a gas target cell, a neutron collimator and a spin processing solenoid. The incident neutron beam was produced by the reaction 2 H( d), n) 3 He at θ lab = 30° . The neutron polarization was P = (42.9 ±0.9)%. Liquid scintillators of C 6H 6 and C 6D 6 were used as scattering targets. Eight neutron detectors allowed the simultaneous measurement of the asymmetry at different angles. The n-p analysing power data were used to perform new phase-shift analyses, including all available n-p scattering data in this energy region. The results for the n-p analysing power at 14.5 MeV were found to be slightly different from the predictions of the Livermore (LRL X) as well as from those of the Yale (Y IV) phase-shift sets. The results for the n-d analysing power at 14.3 MeV show no significant difference to the p-d data at this energy. Three-particle calculations from Dolescball and from Benayoun et al. give reasonable agreement with the experimental data although there are still some minor deviations.