Cross-section model for cold neutron scattering in solid and liquid methane. II: group-constant generation

Cold and thermal neutron scattering in liquid water—II: Scattering laws and group constants for HO and DO

“…The group-constant sets will be utilized for design and analysis of a neutron source and a nuclear reactor. By the combined use of the group constants for liquid 4 He, H 2 ; D 2 ; and CH 4 and solid CH 4 [20][21][22][23][24][25]32,33], it will be possible to proceed with the research and development of advanced pulsed and steady-state sources for ultra-cold, cold and thermal neutrons. …”

“…[22]). The energy range from 0:1 meV to 10 eV is divided at equal logarithmic intervals into G ¼ 80 groups.…”

“…The former may be commonly used in a multi-group neutron transport analysis and the latter in a continuous-energy Monte Carlo calculation. By a combination with the already-generated libraries for liquid H 2 and D 2 and solid CH 4 [19][20][21][22], we may proceed to study design and analysis of an advanced cold-neutron source [23][24][25].…”

Cold neutron production in solid and liquid moderators. II: on the reentrant-hole configuration

“…The resulting neutron fluxes are normalized to one source neutron per unit incident area (i.e., 1 n=cm 2 ). A set of multigroup constants (neutron cross-section library) for solid CH 4 at 20.4 K in cold and epithermal energy range is utilized, which has been generated by Sakurai et al [6] and verified by comparing with many experimental cross-section results [7]. The energy range from 0:1 meV-10 eV is divided at equal logarithmic (lethargy) intervals into 80 groups.…”

“…5 that L ¼ 6 cm is large enough to yield such a reflector effect, i.e., with the surrounding thickness of 2 cm. Since the mean-free-paths for cold and epi-thermal neutrons are about 2 and 6 mm, respectively, [6], such thickness as reflector seems sufficient. This suggests that a porous region near the moderator surface should be surrounded by reflective materials for production and storage of cold neutrons.…”