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Title: Variations in AmLi source spectra and their estimation utilizing the 5 Ring Multiplicity Counter

Active-mode assay systems are widely used for the safeguards of uranium items to verify compliance with the Non-Proliferation Treaty. Systems such as the Active-Well Coincidence Counter (AWCC) and the Uranium Neutron Coincidence Collar (UNCL) use americium-lithium (AmLi) neutron sources to induce fissions which are measured to determine the sample mass. These systems have historically relied on calibrations derived from well-defined standards. Recently, restricted access to standards or more difficult measurements have resulted in a reliance on modeling and simulation for the calibration of systems, which introduces potential simulation biases. Furthermore, the AmLi source energy spectra commonly used in the safeguards community do not accurately represent measurement results and the spectrum uncertainty can represent a large contribution to the total modeling uncertainty in active-mode systems.
 [1] ;  [2] ;  [3] ; ORCiD logo [2]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Univ. of Florida, Gainesville, FL (United States)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  3. Univ. of Florida, Gainesville, FL (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0168-9002; TRN: US1700670
Grant/Contract Number:
AC52-06NA25396; NA0002534
Accepted Manuscript
Journal Name:
Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment
Additional Journal Information:
Journal Volume: 856; Journal Issue: C; Journal ID: ISSN 0168-9002
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA)
Contributing Orgs:
Consortium for Verification Technology
Country of Publication:
United States
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; AmLi spectrum; active interrogation; safeguards; neutron counting
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1397849