Global to push GA events into
skip to main content

Title: Physics-based, Bayesian sequential detection method and system for radioactive contraband

A distributed sequential method and system for detecting and identifying radioactive contraband from highly uncertain (noisy) low-count, radionuclide measurements, i.e. an event mode sequence (EMS), using a statistical approach based on Bayesian inference and physics-model-based signal processing based on the representation of a radionuclide as a monoenergetic decomposition of monoenergetic sources. For a given photon event of the EMS, the appropriate monoenergy processing channel is determined using a confidence interval condition-based discriminator for the energy amplitude and interarrival time and parameter estimates are used to update a measured probability density function estimate for a target radionuclide. A sequential likelihood ratio test is then used to determine one of two threshold conditions signifying that the EMS is either identified as the target radionuclide or not, and if not, then repeating the process for the next sequential photon event of the EMS until one of the two threshold conditions is satisfied.
Inventors:
; ; ; ; ; ; ;
Issue Date:
OSTI Identifier:
1127092
Assignee:
Lawrence Livermore National Security, LLC (Livermore, CA) LLNL
Patent Number(s):
8,676,744
Application Number:
12/259,198
Contract Number:
AC52-07NA27344
Research Org:
LLNL (Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States))
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY

Works referenced in this record:

A probabilistic derivation of gamma-ray attenuation and application: Bayesian mass estimation with a low count spectrum
journal, December 2006
  • Anderson, Dale N.; Hensley, Walter K.; Barnett, Debra S.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 569, Issue 3, p. 894-899
  • DOI: 10.1016/j.nima.2006.09.065

Bayesian estimation of state-space models applied to deconvolution of Bernoulli—Gaussian processes
journal, March 1997

Background removal from spectra by designing and minimising a non-quadratic cost function
journal, April 2005
  • Mazet, Vincent; Carteret, CĂ©dric; Brie, David
  • Chemometrics and Intelligent Laboratory Systems, Vol. 76, Issue 2, p. 121-133
  • DOI: 10.1016/j.chemolab.2004.10.003