US Patent No. 10,557,949

ACCELERATING FISSILE MATERIAL DETECTION WITH A NEUTRON SOURCE


Patent No. 10,557,949
Issue Date February 11, 2020
Title Accelerating Fissile Material Detection With A Neutron Source
Inventorship Mark S Rowland, Livermore, CA (US)
Neal J Snyderman, Livermore, CA (US)
Assignee Lawrence Livermore National Security, LLC, Livermore, CA (US)

Claim of US Patent No. 10,557,949

1. A system for characterizing a radiation source as fissile material or non-fissile material, comprising:a DC power supply comprising an AC filter circuit;
a neutron generator coupled to the DC power supply and configured to irradiate the radiation source by inducing radiation in the radiation source;
a detector configured to receive and count neutrons emitted from the radiation source both naturally and from irradiation by the neutron generator; and
an analyzer component coupled to the detector and configured to measure a number of neutrons simultaneously emitted from the radiation source during a number of measurement time periods to derive a multiplet count distribution, compute the mean count rate of the multiplet count distribution, compute the number of pairs of the multiplet count distribution, use the mean count rate to produce a Poisson distribution for the mean count rate, compute the expected number of pairs for the Poisson distribution, subtract the expected number of pairs for the Poisson distribution from the number of pairs in the measurement, and characterize the radiation source as fissile material if the number of pairs in the measurement exceeds the number of pairs for the Poisson distribution.