Improved Thermal Neutron Scattering Kernels for Liquid Hydrogen and Deuterium

Article type: Research Article

Authors: Granada, J.R. | Gillette, V.H. | Pepe, M.E. | Sbaffoni, M.M.

Affiliations: Comisión Nacional de Energía Atómica, Centro Atómico Bariloche and Instituto Balseiro, 8400 S.C. de Bariloche (RN), Argentina | Comisión Nacional de Energía Atómica, Centro Atómico Constituyentes, 8400 S.C. de Bariloche (RN), Argentina

Note: [] Corresponding author. E-mail: [email protected]

Abstract: Recent experimental information about the dynamics and structure of liquid hydrogen and deuterium has been used to produce new descriptions of the interaction of slow neutrons with these cryogenic moderators. These models were employed as input data to generate new scattering cross-section libraries using the NJOY code. The molecular translational motion, for both diffusive and collective degrees of freedom, has been reanalysed and represented by different spectral frequency distributions compared to those originally built into the code. Recent structural studies of liquid deuterium are considered in the present work, to use a realistic structure factor for the calculation of the scattering law at different temperatures within the ranges corresponding to the liquid phase of H2 and D2. The preliminary validation tests performed so far using the new libraries indicate that they are able to produce results in better agreement with the experiments than the existing ones.

Keywords: Liquid hydrogen, Deuterium, Slow neutrons, NJOY package

DOI: 10.1080/1023816031000100888

Journal: Journal of Neutron Research, vol. 11, no. 1, 2, pp. 25-40, 2003