Cold and thermal neutron scattering cross sections of liquid H2 and D2. II: improvement on coherent scattering

In the previous paper, a cross section model has been developed for cold and thermal neutron scattering in liquid H2 and D2 at temperatures between melting and boiling points. In the present paper, the model is improved to describe adequately coherent scattering in liquid para-H2 and D2 in terms of a mean field approximation. A screened response function and an effective potential are successfully determined by use of an already-ascertained self scattering function and an experimentally-estimated static structure factor. It is shown that the improved model is in good agreement with experimental cross sections, both total and double-differential. This makes it possible to use the model for generation of a reliable cross-section library in developing an advanced cold-neutron source.