TY - JOUR
T1 - Effects of Correlated and Uncorrelated Gamma Rays on Neutron Multiplicity Counting
AU - Cowles, Christian C.
AU - Behling, Richard S.
AU - Imel, George R.
AU - Kouzes, Richard T.
AU - Lintereur, Azaree T.
AU - Robinson, Sean M.
AU - Siciliano, Edward R.
AU - Stave, Sean C.
N1 - Publisher Copyright:
© 1963-2012 IEEE.
PY - 2017/7
Y1 - 2017/7
N2 - Neutron multiplicity counting relies on time correlation between neutron signals to assay the fissile mass, (α,n) to spontaneous fission neutron ratio, and neutron self-multiplication of samples. Gamma-ray sensitive neutron multiplicity counters may misidentify gamma rays as neutrons and therefore miscalculate sample characteristics. Time correlated and uncorrelated gamma-ray-like signals were added into gamma-ray free neutron multiplicity counter data to examine the effects of gamma-ray signals being misidentified as neutron signals on assays. Multiplicity counter measurements with and without gamma-ray-like signals were compared to determine the assay error associated with gamma-ray-like signals at various gamma-ray and neutron rates. Correlated and uncorrelated gamma-ray signals each produced consistent but different measurement errors. Correlated gamma-ray signals most strongly led to fissile mass overestimates, whereas uncorrelated gamma-ray signals most strongly lead to (α,n) neutron overestimates. Accounting for the effects of gamma rays on gamma-ray sensitive neutron multiplicity counters may allow these effects to be compensated for, thus mitigating the assay error associated with misidentified gamma rays.
AB - Neutron multiplicity counting relies on time correlation between neutron signals to assay the fissile mass, (α,n) to spontaneous fission neutron ratio, and neutron self-multiplication of samples. Gamma-ray sensitive neutron multiplicity counters may misidentify gamma rays as neutrons and therefore miscalculate sample characteristics. Time correlated and uncorrelated gamma-ray-like signals were added into gamma-ray free neutron multiplicity counter data to examine the effects of gamma-ray signals being misidentified as neutron signals on assays. Multiplicity counter measurements with and without gamma-ray-like signals were compared to determine the assay error associated with gamma-ray-like signals at various gamma-ray and neutron rates. Correlated and uncorrelated gamma-ray signals each produced consistent but different measurement errors. Correlated gamma-ray signals most strongly led to fissile mass overestimates, whereas uncorrelated gamma-ray signals most strongly lead to (α,n) neutron overestimates. Accounting for the effects of gamma rays on gamma-ray sensitive neutron multiplicity counters may allow these effects to be compensated for, thus mitigating the assay error associated with misidentified gamma rays.
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U2 - 10.1109/TNS.2017.2667407
DO - 10.1109/TNS.2017.2667407
M3 - Article
AN - SCOPUS:85029062850
SN - 0018-9499
VL - 64
SP - 1865
EP - 1870
JO - IEEE Transactions on Nuclear Science
JF - IEEE Transactions on Nuclear Science
IS - 7
M1 - 7867089
ER -