High-Precision Method for Revealing Hidden Substances by Means of Tagged Neutrons

Abstract

A new method of employing A(n, n′γ)A reactions of inelastic tagged-neutron scattering is proposed for revealing hidden substances. In contrast to the well-known method where substances are identified by measuring the spectrum of gamma rays, the new method consists in identifying substances by measuring the spectrum of neutrons. The neutron energy is measured by the time-of-flight method via detecting a (γ, n) pair and invoking the parameters of tagged neutrons. The detection of a neutron in a pair with a photon is also a factor that reduces the rate of accumulation of useful events. As is shown in the present study, however, the method in question possesses a number of important special features owing to which it boasts high precision and efficiency, as well as the ability of revealing a broad range of elements and hidden substances of small volume. A numerical simulation of both methods is performed. It is shown that the required time of measurements within the proposed method is one order of magnitude shorter, which makes it possible to circumvent that main difficulty encountered in applying the known method and associated with a low resource and a high cost of neutron sources.