The study on the detecting technique of high-enrichment uranium by active coincidence neutron count

A small column of Uranium fission material, which contains 90.34% 235U, is detected by active coincidence neutron counting in this study. An active well coincidence counter is used to measure the fission neutrons from 235u induced by Am-Li neutron source. The linear correlation coefficient comes to 0.999 after a linear recombination is performed between the mass of uranium metal and real coincidence counts rate, total neutron counts rate calculated by least square method respectively. Further more, it is determined the trend of neutron counts varying with different sample shapes, the distances between neutron source and sample while keeping the Uranium quality a constant. (authors)