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

Weinmann-Smith, Robert; Beddingfield, David H.; Enqvist, Andreas; Swinhoe, Martyn Thomas

doi:10.1016/j.nima.2017.02.083

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

Abstract

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.

Authors:

Weinmann-Smith, Robert ^[1]; Beddingfield, David H. ^[2]; Enqvist, Andreas ^[3];

^[2]

Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Univ. of Florida, Gainesville, FL (United States)
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Univ. of Florida, Gainesville, FL (United States)

Publication Date:: Tue Feb 28 00:00:00 EST 2017

Research Org.:: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

Contributing Org.:: Consortium for Verification Technology

OSTI Identifier:: 1345948

Alternate Identifier(s):: OSTI ID: 1397849

Report Number(s):: LA-UR-17-20416
Journal ID: ISSN 0168-9002; TRN: US1700670

Grant/Contract Number:: AC52-06NA25396; NA0002534

Resource Type:: 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

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; AmLi spectrum; active interrogation; safeguards; neutron counting

Citation Formats


                    Weinmann-Smith, Robert, Beddingfield, David H., Enqvist, Andreas, and Swinhoe, Martyn Thomas. Variations in AmLi source spectra and their estimation utilizing the 5 Ring Multiplicity Counter.  United States: N. p., 2017. 
Web.  doi:10.1016/j.nima.2017.02.083.

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                    Weinmann-Smith, Robert, Beddingfield, David H., Enqvist, Andreas, & Swinhoe, Martyn Thomas. Variations in AmLi source spectra and their estimation utilizing the 5 Ring Multiplicity Counter.  United States.  https://doi.org/10.1016/j.nima.2017.02.083

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                    Weinmann-Smith, Robert, Beddingfield, David H., Enqvist, Andreas, and Swinhoe, Martyn Thomas. Tue .  
"Variations in AmLi source spectra and their estimation utilizing the 5 Ring Multiplicity Counter".  United States.  https://doi.org/10.1016/j.nima.2017.02.083.  https://www.osti.gov/servlets/purl/1345948.

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@article{osti_1345948,

  title        = {Variations in AmLi source spectra and their estimation utilizing the 5 Ring Multiplicity Counter},

  author       = {Weinmann-Smith, Robert and Beddingfield, David H. and Enqvist, Andreas and Swinhoe, Martyn Thomas},

  abstractNote = {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.},

  doi          = {10.1016/j.nima.2017.02.083},

  journal      = {Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment},

  number       = C,

  volume       = 856,

  place        = {United States},

  year         = {Tue Feb 28 00:00:00 EST 2017},

  month        = {Tue Feb 28 00:00:00 EST 2017}

}

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Works referenced in this record:

Measurement of the 241Am–Li radionuclide neutron source spectrum
journal, September 2003

Tagziria, H.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 510, Issue 3
DOI: 10.1016/S0168-9002(03)01825-4

Measurement and Monte Carlo modelling of the JRC 241Am-Li( ,n) source spectrum
journal, August 2004

Tagziria, H.; Wiegel, B.; Klein, H.
Radiation Protection Dosimetry, Vol. 110, Issue 1-4
DOI: 10.1093/rpd/nch189

The Spectrum of Neutrons from A 238Pu-Li Source
journal, January 1981

Ing, H.; Cross, W. G.; Tymons, B. J.
Health Physics, Vol. 40, Issue 3
DOI: 10.1097/00004032-198103000-00008

The ideal neutron energy spectrum of 241AmLi(α,n)10B sources
journal, October 2012

Tagziria, H.; Looman, M.
Applied Radiation and Isotopes, Vol. 70, Issue 10
DOI: 10.1016/j.apradiso.2012.07.008

Works referencing / citing this record:

Simulation of the Nondestructive Assay of ²³⁷ Np Using Active Neutron Multiplicity Counting
journal, September 2019

Hua, Michael Y.; Goddard, Braden; Lloyd, Cody
Nuclear Science and Engineering, Vol. 194, Issue 2
DOI: 10.1080/00295639.2019.1654329

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