Measuring hydrogen with fast neutrons: Application to organic materials identification in cargo containers - CEA - Commissariat à l’énergie atomique et aux énergies alternatives Accéder directement au contenu
Article Dans Une Revue Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment Année : 2020

Measuring hydrogen with fast neutrons: Application to organic materials identification in cargo containers

Résumé

To inspect cargo containers, X-ray imaging can be complemented by fast neutron interrogation to provide indication concerning the chemical nature of the transported goods through the detection of neutron-induced gamma rays. Organic goods are of special interest since they constitute a significant part of the merchandises. In addition, in the context of NRBC-E threats search in cargo containers, a nondestructive inspection system should also be able to detect explosives. Until now, fast neutron interrogation systems identify organic materials in cargo containers using characteristic neutron-induced gamma-ray peaks of carbon, oxygen and nitrogen. However, identifying organics in this way can lead to ambiguities, since no hydrogen gamma ray can be measured with fast neutrons. Nevertheless, it is known that hydrogen strongly modifies the neutron energy spectrum, which in turn affects the amplitudes of gamma-ray peaks. The link between the hydrogen fraction and the amplitude of gamma ray peaks being complex, no attempt has been made to inverse this link until now. Simulations show, however, that a neural network that takes as inputs the heights of carbon, oxygen and nitrogen gamma ray peaks can indeed determine the hydrogen fraction. Simulations of realistic cases show that the use of a neural network indeed allows identifying compounds having similar fractions of carbon, oxygen and nitrogen but different hydrogen fraction, thus opening the way to more accurate materials identification.
Fichier principal
Vignette du fichier
201900002373.pdf (1.2 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Loading...

Dates et versions

cea-02562320 , version 1 (04-05-2020)

Identifiants

Citer

C. Carasco, B. Perot, A. Sardet. Measuring hydrogen with fast neutrons: Application to organic materials identification in cargo containers. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2020, 951, pp.163030. ⟨10.1016/j.nima.2019.163030⟩. ⟨cea-02562320⟩

Collections

CEA DEN CEA-DRF
43 Consultations
214 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More