Development of Neutron Resonance Densitometry

Year
2014
Author(s)
H. Harada - Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency
H. Tsuchiya - Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency
J. Takamine - Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency
H. Iimura - Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency
M. Seya - Integrated Support Center for Nuclear Nonproliferation and Nuclear Security, Japan Atomic Energy Agency
P Schillebeeckx - EC-JRC-IRMM
B. Becker - EC-JRC-IRMM
S. Kopecky - EC-JRC-IRMM
K. Kauwenberghs - EC-JRC-IRMM
A. Moens - EC-JRC-IRMM
W. Mondelaers - EC-JRC-IRMM
A. Kimura - Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency
Abstract
Neutron resonance densitometry (NRD) is a high-speed and accurate non-destructive analysis method, which was proposed to quantify nuclear materials in particle-like debris of melted fuel formed in severe accidents of nuclear reactors such as the Fukushima Daiichi nuclear power plants. NRD uses in combination both neutron resonance transmission analysis (NRTA) and neutron resonance capture analysis (NRCA). NRTA is used to quantify nuclear materials, and NRCA to identify unknown materials mixed in an object. A specially designed gamma-ray spectrometer made of LaBr3 detectors is under development for NRCA in order to utilize to analysis of highly radioactive materials. In order to study the performance of NRD, Monte Carlo simulations have been performed. Furthermore, NRD experiments have been performed at the time-of-flight facility GELINA (Geel Electron LINear Accelerator) of the EC-JRC-IRMM to verify the simulations. The resonance shape analysis code REFIT was used to analyze the experimental data. In this contribution, the progress is reviewed on the development of NRD. Especially, the importance of resonance shape analysis taking into account heterogeneous effect on sample is stressed together with verification experiments.