MEASUREMENT OF THE EFFECTIVE DELAYED-NEUTRON DOSE BY THE α-ROSSI METHOD IN WATER-CONTAINING MEDIA

摘要

A modified method of determining the effective delayed-neutron dose is proposed. The method is based on a combination of determining the pseudoreactivity of the ~(252)Cf source and measuring the α-Rossi time distribution. The advantage of the method proposed here is that there is no need to measure the absolute rate of fissioning of the nuclei in the medium. It is proposed that the latter be expressed in terms of the intensity of a known source of spontaneous fissions of ~(252)Cf nuclei. The measurements are performed on an assembly with a hydrogen-containing moderator. The influence of the positions of the detectors (~3He counters) on the measured effective delayed-neutron fraction is studied.