A.M. LaFleur, W.S. Charlton, H.O. Menlove, and M. Swinhoe,
"Use of Self-Interrogation Neutron Resonance Densitometry (SINRD) to Measure the Fissile Content in Nuclear Fuel,"
Proceedings of 49th Annual INMM Meeting
, Nashville, TN, July 13-17, 2008.
We investigated a new method to verify the concentration of
fissile material in a PWR fresh fuel assembly using
Self-Interrogation Neutron Resonance Densitometry (SINRD). Monte
Carlo NParticle eXtended transport code (MCNPX) was used to
simulate these measurements. The sensitivity of SINRD is based on
using the same fissile materials in the fission chambers as are
under investigation because the effect of resonance absorption
lines in the transmitted flux are amplified by the corresponding
(n,f) reaction peaks in fission chamber. This simulation utilizes
the 238U spontaneous fission neutrons to self-interrogate the fuel
pins. The amount of resonance absorption of these neutrons in the
fuel can be measured using 235U fission chambers placed adjacent to
the assembly. We used ratios of different fission chambers to
reduce the sensitivity of the measurements to extraneous material
present in fuel. The development of SINRD to measure the fissile
content in spent fuel is of great importance to nuclear safeguards
and accountability. Future work includes the use of this technique
to measure the concentration of fissile materials in spent fuel and
pyroprocessing heavy metal product.
Associated Project(s):Development of Self-Interrogation Neutron Resonance Densitometry (SINRD) to Measure the Fissile Content in Nuclear Fuel