Temperature effects and resonance elastic cross section influence on secondary energy distributions of scattered neutrons in the resolved resonance region

It is customary to neglect the effect of thermal motion (Doppler effect) and resonance behavior of elastic cross section on the energy distribution of scattered neutrons in the resonance region. But as has been shown earlier for 238U, there is certain effect of replacing usual step-function by more exact expression, where σs has resonance behavior The question of interest was to check the effect of replacing step distribution by more exact one for the simplest cylindrical two-zone cell with different Vmod / Vf. A code has been written to solve slowing-down equation from unit source in ultra-fine energy scale with two different kernels. Energy averaged cross sections were calculated for 238U and 235U. (authors)