New measurements of the H(n,n)H angular distribution

Measurements have been made of the shape of the hydrogen differential neutron scattering cross section standard at 10 MeV neutron energy. The data were obtained at the Institute of Nuclear and Particle Physics at Ohio University using the D(d,n) reaction as the neutron source. Two different thin films of polypropylene mounted on tantalum backings were used as the hydrogenous samples in this experiment. Preliminary data obtained with the thicker film will be reported here. Two independent computer-based data acquisition systems were used to obtain the data which were stored in a multi-parameter mode so that analysis could be done under different conditions after the experiment was finished. The differential cross section was measured simultaneously at 11 laboratory angles (0 degrees, +/- 12 degrees, +/- 24 degrees, +/- 36 degrees, +/- 48 degrees and +/- 60 degrees) using DeltaE-E solid state detector telescopes in an evacuated scattering chamber. The data are in better agreement with the Arndt evaluation than the ENDF/B-VI and ENDF/B-V evaluations.