The neutron moderation theory, taking into account a moderating medium temperature

In this paper, in the framework of the gas model, based on the solution of the kinematic problem of the neutron elastic scattering on the nucleus in the “L” system in the general case, that is, when prior to the scattering not only the neutron, but also the kernel has an arbitrary given velocity vector in the “L” system, an analytical expression for the neutron scattering law was first obtained, which includes the temperature moderating medium as a parameter, as well as there were received flux densities and neutron decay spectra for an isotropic neutron source in the reactor medium, also dependent on the temperature of environment and fair for all neutron energy spectrum division (excluding energy of interatomic or intermolecular interactions for moderating medium, if necessary to go beyond the gas model). The expressions obtained for the spectrums of moderating neutrons allow reinterpreting the physical nature of the processes that determine the form of the neutron spectrum in the thermal neutrons.