skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Combined Photoneutron And X Ray Interrogation Of Containers For Nuclear Materials

Abstract

Effective cargo inspection systems for nuclear material detection require good penetration by the interrogating radiation, generation of a sufficient number of fissions, and strong and penetrating detection signatures. Inspection systems need also to be sensitive over a wide range of cargo types and densities encountered in daily commerce. Thus they need to be effective with highly hydrogenous cargo, where neutron attenuation is a major limitation, as well as with dense metallic cargo, where x-ray penetration is low. A system that interrogates cargo with both neutrons and x-rays can, in principle, achieve high performance over the widest range of cargos. Moreover, utilizing strong prompt-neutron ({approx}3 per fission) and delayed-gamma ray ({approx}7 per fission) signatures further strengthens the detection sensitivity across all cargo types. The complementary nature of x-rays and neutrons, used as both probing radiation and detection signatures, alleviates the need to employ exceedingly strong sources, which would otherwise be required to achieve adequate performance across all cargo types, if only one type of radiation probe were employed. A system based on the above principles, employing a commercially-available 9 MV linac was developed and designed. Neutrons are produced simultaneously with x-rays by the photonuclear interaction of the x-ray beam with amore » suitable converter. A total neutron yield on the order of 10{sup 11} n/s is achieved with an average electron beam current of 100 {mu}A. If fissionable material is present, fissions are produced both by the high-energy x-ray beam and by the photoneutrons. Photofission and neutron fission dominate in hydrogenous and metallic cargos, respectively. Neutron-capture gamma rays provide information on the cargo composition. The prompt neutrons resulting from fission are detected by two independent detector systems: by very efficient Differential Die Away Analysis (DDAA) detectors, and by direct detection of neutrons with energies higher than 3 MeV using a recently developed fluorine-based threshold activation detector (TAD). The delayed gamma-ray signals are measured with high efficiency with the same TAD and with additional lower-cost plastic scintillators.« less

Authors:
; ; ; ; ; ;  [1]
  1. Rapiscan Laboratories, Inc., 520 Almanor Ave., Sunnyvale, CA 94085 (United States)
Publication Date:
OSTI Identifier:
21513447
Resource Type:
Journal Article
Journal Name:
AIP Conference Proceedings
Additional Journal Information:
Journal Volume: 1336; Journal Issue: 1; Conference: CAARI 2010: 21. International Conference on the Application of Accelerators in Research and Industry, Fort Worth, TX (United States), 8-13 Aug 2010; Other Information: DOI: 10.1063/1.3586190; (c) 2011 American Institute of Physics; Journal ID: ISSN 0094-243X
Country of Publication:
United States
Language:
English
Subject:
07 ISOTOPES AND RADIATION SOURCES; ACTIVATION DETECTORS; CAPTURE; CARGO; CONTAINERS; DENSITY; ELECTRON BEAMS; FISSIONABLE MATERIALS; FLUORINE; GAMMA RADIATION; LINEAR ACCELERATORS; MEV RANGE 01-10; NEUTRON REACTIONS; PHOTOFISSION; PHOTONEUTRONS; PLASTIC SCINTILLATORS; POSITION SENSITIVE DETECTORS; PROMPT NEUTRONS; X RADIATION; ACCELERATORS; BARYON REACTIONS; BARYONS; BEAMS; ELECTROMAGNETIC RADIATION; ELEMENTARY PARTICLES; ELEMENTS; ENERGY RANGE; FERMIONS; FISSION; FISSION NEUTRONS; HADRON REACTIONS; HADRONS; HALOGENS; IONIZING RADIATIONS; LEPTON BEAMS; MATERIALS; MEASURING INSTRUMENTS; MEV RANGE; NEUTRON DETECTORS; NEUTRONS; NONMETALS; NUCLEAR REACTIONS; NUCLEON REACTIONS; NUCLEONS; PARTICLE BEAMS; PHOSPHORS; PHOTONUCLEAR REACTIONS; PHOTONUCLEONS; PHYSICAL PROPERTIES; RADIATION DETECTORS; RADIATIONS

Citation Formats

Gozani, Tsahi, Shaw, Timothy, King, Michael J, Stevenson, John, Elsalim, Mashal, Brown, Craig, and Condron, Cathie. Combined Photoneutron And X Ray Interrogation Of Containers For Nuclear Materials. United States: N. p., 2011. Web. doi:10.1063/1.3586190.
Gozani, Tsahi, Shaw, Timothy, King, Michael J, Stevenson, John, Elsalim, Mashal, Brown, Craig, & Condron, Cathie. Combined Photoneutron And X Ray Interrogation Of Containers For Nuclear Materials. United States. https://doi.org/10.1063/1.3586190
Gozani, Tsahi, Shaw, Timothy, King, Michael J, Stevenson, John, Elsalim, Mashal, Brown, Craig, and Condron, Cathie. Wed . "Combined Photoneutron And X Ray Interrogation Of Containers For Nuclear Materials". United States. https://doi.org/10.1063/1.3586190.
@article{osti_21513447,
title = {Combined Photoneutron And X Ray Interrogation Of Containers For Nuclear Materials},
author = {Gozani, Tsahi and Shaw, Timothy and King, Michael J and Stevenson, John and Elsalim, Mashal and Brown, Craig and Condron, Cathie},
abstractNote = {Effective cargo inspection systems for nuclear material detection require good penetration by the interrogating radiation, generation of a sufficient number of fissions, and strong and penetrating detection signatures. Inspection systems need also to be sensitive over a wide range of cargo types and densities encountered in daily commerce. Thus they need to be effective with highly hydrogenous cargo, where neutron attenuation is a major limitation, as well as with dense metallic cargo, where x-ray penetration is low. A system that interrogates cargo with both neutrons and x-rays can, in principle, achieve high performance over the widest range of cargos. Moreover, utilizing strong prompt-neutron ({approx}3 per fission) and delayed-gamma ray ({approx}7 per fission) signatures further strengthens the detection sensitivity across all cargo types. The complementary nature of x-rays and neutrons, used as both probing radiation and detection signatures, alleviates the need to employ exceedingly strong sources, which would otherwise be required to achieve adequate performance across all cargo types, if only one type of radiation probe were employed. A system based on the above principles, employing a commercially-available 9 MV linac was developed and designed. Neutrons are produced simultaneously with x-rays by the photonuclear interaction of the x-ray beam with a suitable converter. A total neutron yield on the order of 10{sup 11} n/s is achieved with an average electron beam current of 100 {mu}A. If fissionable material is present, fissions are produced both by the high-energy x-ray beam and by the photoneutrons. Photofission and neutron fission dominate in hydrogenous and metallic cargos, respectively. Neutron-capture gamma rays provide information on the cargo composition. The prompt neutrons resulting from fission are detected by two independent detector systems: by very efficient Differential Die Away Analysis (DDAA) detectors, and by direct detection of neutrons with energies higher than 3 MeV using a recently developed fluorine-based threshold activation detector (TAD). The delayed gamma-ray signals are measured with high efficiency with the same TAD and with additional lower-cost plastic scintillators.},
doi = {10.1063/1.3586190},
url = {https://www.osti.gov/biblio/21513447}, journal = {AIP Conference Proceedings},
issn = {0094-243X},
number = 1,
volume = 1336,
place = {United States},
year = {2011},
month = {6}
}