Neutron Emission Characteristics of Two Mixed-Oxide Fuels: Simulations and Initial Experiments

Chichester, D. L. ; Pozzi, S. A. ; Dolan, J. L. ; Flaska, M. ; Johnson, J. T. ; Seabury, E. H. ; Gantz, E. M.

Idaho National Laboratory

关键词: 46 Instrumentation Related To Nuclear Science And Technology;    Neutron Spectroscopy;    Energy Spectra;    Actinides;    Wave Forms Coincidence;   

DOI  :  10.2172/968682
RP-ID  :  INL/EXT-09-16566
RP-ID  :  DE-AC07-05ID14517
RP-ID  :  968682

美国|英语

来源: UNT Digital Library

【 摘 要 】

Simulations and experiments have been carried out to investigate the neutron emission characteristics of two mixed-oxide (MOX) fuels at Idaho National Laboratory (INL). These activities are part of a project studying advanced instrumentation techniques in support of the U.S. Department of Energy's Fuel Cycle Research and Development program and it's Materials Protection, Accounting, and Control for Transmutation (MPACT) campaign. This analysis used the MCNP-PoliMi Monte Carlo simulation tool to determine the relative strength and energy spectra of the different neutron source terms within these fuels, and then used this data to simulate the detection and measurement of these emissions using an array of liquid scintillator neutron spectrometers. These calculations accounted for neutrons generated from the spontaneous fission of the actinides in the MOX fuel as well as neutrons created via (alpha,n) reactions with oxygen in the MOX fuel. The analysis was carried out to allow for characterization of both neutron energy as well as neutron coincidences between multiple detectors. Coincidences between prompt gamma rays and neutrons were also analyzed. Experiments were performed at INL with the same materials used in the simulations to benchmark and begin validation tests of the simulations. Data was collected in these experiments using an array of four liquid scintillators and a high-speed waveform digitizer. Advanced digital pulse-shape discrimination algorithms were developed and used to collect this data. Results of the simulation and modeling studies are presented together with preliminary results from the experimental campaign.