Measurement of Prompt Neutron Lifetime in ZED-2

Abstract

This paper presents results from a measurement of prompt neutron lifetime in ZED-2. An experimental method that mimics the 1/v method of calculating prompt neutron lifetime was used to determine it by combining critical height data obtained by poisoning the ZED-2 moderator using boric acid along with a measurement of the level coefficient of reactivity at critical for the unpoisoned reactor.The experimentally determined value is compared to an MCNP calculation of prompt neutron lifetime using the alpha-static method. The agreement is very good, with the discrepancy between calculation and experiment being under 0.3 percent compared to an experimental uncertainty of 1.9 percent.