Accession Number : AD0274572

Title :   A MONTE CARLO STUDY OF RESONANCE ESCAPE PROBABILITY IN HETEROGENEOUS SLAB LATTICES CONTAINING RESONANT ABSORBERS AND SCATTERERS

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION WASHINGTON D C

Personal Author(s) : Schneider ,Harold ; Levitt ,Leo ; Sroub,Kevin J.

Report Date : APR 1962

Pagination or Media Count : 94

Abstract : Resonance escape probabilities for heterogeneous semi-infinite slab lattice systems were computed by the Monte Carlo method in the energy range 1 kilo-electron-volt to 0.125 electron volt. Absorber-moderator combinations considered were W-H2O, W-LiH, W-BeO, Au-H2O, Au-LiH, and Au-BeO. Absorber and moderator thickness and absorber temperature were varied in a parametric study. The Monte Carlo results of neutron absorption for various thicknesses of tungsten and gold slabs at room temperature are in good agreement with previous experimental results. The calculations show the dominating influence of resonance peaks in the absorption of thin samples. With increasing thickness this peak absorption saturates out, and considerably more absorption occurs in the wings of the resonances. Strong resonance scattering in several tungsten resonances results in greater self-shielding than would exist if the scattering were absent. (Author)

Descriptors :   *COMPUTER LOGIC, *NEUTRON CROSS SECTIONS, *NEUTRON SCATTERING, *NUMERICAL METHODS AND PROCEDURES, *PROBABILITY, ABSORPTION, BERYLLIUM COMPOUNDS, CODING, COMPUTERS, CRYSTAL LATTICES, ENERGY, GOLD, HYDRIDES, LITHIUM COMPOUNDS, MONTE CARLO METHOD, OXIDES, RESEARCH REACTORS, RESONANCE, STATISTICAL ANALYSIS, TUNGSTEN, WATER

Distribution Statement : APPROVED FOR PUBLIC RELEASE