EVALUATION OF COLD NEUTRON-SCATTERING CROSS-SECTIONS FOR LIGHT AND HEAVY-WATER

Cross section models for cold and thermal neutron scattering from ligh t and heavy water are developed. They are based on the proper treatmen t of molecular motions in the water in terms of the diffusive and osci llatory translational motions of a water molecule and the intermolecul ar space-time correlations for highly bonded molecules. Intramolecular motions such as hindered rotations and internal harmonic vibrations a re also included. The total and differential scattering cross sections are calculated for a wide range of incident neutron energies from ver y cold to epithermal. Good agreement with available experimental resul ts permits us to generate basic cross section libraries for the evalua tion of cold and ultracold neutron production.