Calculations by TRIPOLI of the neutron spectrum in the lower sections of the PHENIX exchanger

Calculations were made to determine the contribution to the activation of the secondary sodium by the neutrons which escape from beneath the side neutron shield of the PHENIX reactor. In the course of this study we have also determined the complete energy spectrum from all points of view of the neutron pathways in order to compare results with those given by other methods. These latter calculations were useless as far as the activation of the secondary sodium was involved since this latter item is due only to the small numbers of neutrons which can get through the shield and still have sufficient energy. The deviations between the results given by TRIPOLI and NIOBE are due for the most part to the very different conditions under which they were calculated. The results are given. (auth)