Measurement and Characterization of Advanced Nuclear Fuels at the Idaho National Laboratory Through Neutron Energy Spectrum Unfolding

Results are presented on the ability to perform neutron energy spectroscopy with standard organic scintillation detectors. Well-established pulse-shape discrimination techniques are used to reject the detectors¶ gamma-ray signal and produce neutron pulse-height distributions. These distributions are µXQIROGHG¶??XVLQJ??a detector-specific response matrix to obtain the incident neutron energy spectrum. Unfolding results are introduced for the measurements and characterization of mixed-oxide fuel pins. The robust measurement system used to perform these measurements included four EJ-309 liquid scintillation detectors with a 250-MHz, 12-bit waveform digitizer. The MCNP-PoliMi Monte Carlo particle transport code was used to build the mixed-oxide fuel source and develop an anticipated neutron energy distribution.