Slow Neutron Scattering from Water

Neutrons of 0.05-eV energy were inelastically scattered from samples of water. The experiment was arranged so that a correction could be made for multiple scattering and so that the observed scattering law would be measured at momentum change ℏκ smaller than obtained in previous experiments. From the data, it is concluded that 1) at these low κ values the scattering law at fixed β is proportional to κ as predicted by the McMurry-Russell model but by no other models, 2) discrete transitions are no more distinct at these smaller κ's than at larger κ's contrary to the predictions of the McMurry-Russell model, and 3) multiple scattering is important but not as large as predicted and that experimental corrections for it can be made.