Extension of the Dytlewskistyle dead time correction formalism for neutron multiplicity counting to any order
Here, neutron multiplicity counting using shiftregister calculus is an established technique in the science of international nuclear safeguards for the identification, verification, and assay of special nuclear materials. Typically passive counting is used for Pu and mixed PuU items and active methods are used for U materials. Three measured counting rates, singles, doubles and triples are measured and, in combination with a simple analytical pointmodel, are used to calculate characteristics of the measurement item in terms of known detector and nuclear parameters. However, the measurement problem usually involves more than three quantities of interest, but even in cases where the next higher order count rate, quads, is statistically viable, it is not quantitatively applied because corrections for dead time losses are currently not available in the predominant analysis paradigm. In this work we overcome this limitation by extending the commonly used dead time correction method, developed by Dytlewski, to quads. We also give results for pents, which may be of interest for certain special investigations. Extension to still higher orders, may be accomplished by inspection based on the sequence presented. We discuss the foundations of the Dytlewski method, give limiting cases, and highlight the opportunities and implications that these newmore »
 Authors:

^{[1]};
^{[2]}
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Publication Date:
 Report Number(s):
 LAUR1720319
Journal ID: ISSN 01689002; TRN: US1702545
 Grant/Contract Number:
 AC5206NA25396
 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: 869; Journal Issue: C; Journal ID: ISSN 01689002
 Publisher:
 Elsevier
 Research Org:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org:
 USDOE National Nuclear Security Administration (NNSA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; neutron coincidence counting; neutron multiplicity counting; dead time corrections
 OSTI Identifier:
 1372798
Croft, Stephen, and Favalli, Andrea. Extension of the Dytlewskistyle dead time correction formalism for neutron multiplicity counting to any order. United States: N. p.,
Web. doi:10.1016/j.nima.2017.06.032.
Croft, Stephen, & Favalli, Andrea. Extension of the Dytlewskistyle dead time correction formalism for neutron multiplicity counting to any order. United States. doi:10.1016/j.nima.2017.06.032.
Croft, Stephen, and Favalli, Andrea. 2017.
"Extension of the Dytlewskistyle dead time correction formalism for neutron multiplicity counting to any order". United States.
doi:10.1016/j.nima.2017.06.032. https://www.osti.gov/servlets/purl/1372798.
@article{osti_1372798,
title = {Extension of the Dytlewskistyle dead time correction formalism for neutron multiplicity counting to any order},
author = {Croft, Stephen and Favalli, Andrea},
abstractNote = {Here, neutron multiplicity counting using shiftregister calculus is an established technique in the science of international nuclear safeguards for the identification, verification, and assay of special nuclear materials. Typically passive counting is used for Pu and mixed PuU items and active methods are used for U materials. Three measured counting rates, singles, doubles and triples are measured and, in combination with a simple analytical pointmodel, are used to calculate characteristics of the measurement item in terms of known detector and nuclear parameters. However, the measurement problem usually involves more than three quantities of interest, but even in cases where the next higher order count rate, quads, is statistically viable, it is not quantitatively applied because corrections for dead time losses are currently not available in the predominant analysis paradigm. In this work we overcome this limitation by extending the commonly used dead time correction method, developed by Dytlewski, to quads. We also give results for pents, which may be of interest for certain special investigations. Extension to still higher orders, may be accomplished by inspection based on the sequence presented. We discuss the foundations of the Dytlewski method, give limiting cases, and highlight the opportunities and implications that these new results expose. In particular there exist a number of ways in which the new results may be combined with other approaches to extract the correlated rates, and this leads to various practical implementations.},
doi = {10.1016/j.nima.2017.06.032},
journal = {Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment},
number = C,
volume = 869,
place = {United States},
year = {2017},
month = {7}
}