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In this article measured time-of-flight spectra and energy spectra of a water moderator operated at various temperatures between 20K and room temperature are described. These data are used to validate generated and processed neutron scattering law data. It was possible to simulate the leakage spectrum of a water moderator at cryogenic temperatures and compare it with experimental results.

For the relevant materials used in cold and superthermal neutron sources the database for design studies was considerably improved. For D 2 O at room temperature the intra and inter molecular interaction with neutrons were included using realistic structure factors S ( κ ). These effects are also taken into account for the cold moderators liquid H 2 and D 2 by deriving improved S ( κ ). The neutron interaction in solid materials and neutron filters as Al, Pb and Bi is treated exactly at low temperatures, especially for coherent neutron scattering in the tetragonal and FCC lattices. For superfluid 4 He cross-section data for ultracold neutron production were derived as well as data for neutron transport considering diffusive motions and intermolecular scattering. Validation of the generated cross-sectional data was realized by comparison with differential and integral neutron scattering experiments so far available. These thermal neutron data can be used for both multigroup S N and Monte-Carlo methods solving the neutron transport equation.

Scattering laws S(α,β) were derived in ENDF-6 format for the most important materials as liquid H2, D2, 4He and solid Be, Bi used in cold and superthermal neutron sources by considering the incoherent as well as the coherent scattering dynamics at working temperature. For cold and superthermal neutron source design calculations including the determination of heat production coupled n-γ cross-section matrices and Kerma factors were generated.