Preliminary Delayed Gamma-Ray Spectroscopy for Non-Destructive Analysis of Fissionable Material

Year
2015
Author(s)
Mitsuo Koizumi - Japan Atomic Energy Agency
Jun Takamine - Japan Atomic Energy Agency
M. Seya - Integrated Support Center for Nuclear Nonproliferation and Nuclear Security, Japan Atomic Energy Agency
Willy Mondelaers - Institute for Reference Materials and Measurements
B. Pedersen - Institute for Transuranium Elements (ITU)
Jan Heyse - Institute of Reference Materials and Measurements, Joint Research Center
Abstract
There is a growing interest regarding how to effectively safeguard nuclear materials (NM), specifically how to efficiently determine the composition of mixed materials. Currently re- searchers of the JAEA and JRC (ITU, Ispra, and IRMM, Geel) are discussing the development of a non-destructive analysis system using a pulsed DT neutron source. The system will uti- lize a combination of Differential Die-Away Analysis (DDA), Neutron Resonance Transmission Analysis (NRTA), Prompt Gamma-ray Analysis (PGA), and Delayed Gamma-ray Spectroscopy (DGS) techniques. Of specific interest is applying this system toward determining the Pu/U composition of purified MOX fuel and non-purified NM with high radioactivity (e.g. spent fuel, vitrified waste, melted fuel from reactor accidents, and next-generation fuel cycle materials). The DGS technique has the potential to establish fissionable material ratios to relatively high precision since each fissionable isotope has a unique fission yield. These fission products gener- ate specific, time-dependent, gamma-ray energy spectra that extend well above 3 MeV, which is a benefit when applied to the NM of interest that have high passive gamma-ray emissions below this energy. This presentation will describe initial studies regarding the precision that the DGS portion of this system can obtain and how it will be used in conjunction with the other techniques to analyze the composition of the NM of interest.