Cold and thermal neutron scattering cross sections of liquid H2 and D2 at temperatures between melting and boiling points

Cross section models for neutron scattering in liquid H2 and D2 are presented which are applicable to a wide range of incident energies from 0.1 meV to 10 eVat all practical tempera- tures between the melting and boiling points. Typical cross-section results both double- di¡erential and total are calculated to con¢rm the e¡ects of nuclear spin correlations i.e. ortho and para and molecular translations and rotations. A slowing-down property is also analyzed in terms of the average cosine of scattering angle and the average energy of scat- tered neutrons. It is shown that the present models are able to serve for the generation of basic cross-section ¢le in developing and advanced neutron source.