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Title: Systematic measurement of fast neutron background fluctuations in an urban area using a mobile detection system

Abstract

Neutron background measurements using a mobile trailer-based system were conducted in Knoxville, Tennessee. The 0.5 m2 system consisting of 8 EJ-301 liquid scintillation detectors was used to collect neutron background measurements in order to better understand the systematic background variations that depend solely on the street-level measurement position in a local, downtown area. Data was collected along 5 different streets in the downtown Knoxville area, and the measurements were found to be repeatable. Using 10-min measurements, fractional uncertainty in each measured data point was <2%. Compared with fast neutron background count rates measured away from downtown Knoxville, a reduction in background count rates ranging from 10-50% was observed in the downtown area, sometimes varying substantially over distances of tens of meters. These reductions are attributed to the shielding of adjacent buildings, quantified in part here by the metric angle-of-open-sky. The adjacent buildings may serve to shield cosmic ray neutron flux.

Authors:
 [1];  [1];  [2];  [2];  [1];  [3]
  1. Univ. of Tennessee, Knoxville, TN (United States). Department of Nuclear and Radiological Engineering
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  3. Univ. of Tennessee, Knoxville, TN (United States). Department of Nuclear and Radiological Engineering; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1162069
Grant/Contract Number:  
AC05-00OR22725; HSHQDC-10-X-00662
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: 773; Journal ID: ISSN 0168-9002
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; Fast neutron; Background radiation; Passive detection; Liquid scintillation detectors; Standoff detection

Citation Formats

Iyengar, Anagha, Beach, Matthew, Newby, Robert J., Fabris, Lorenzo, Heilbronn, Lawrence H., and Hayward, Jason P. Systematic measurement of fast neutron background fluctuations in an urban area using a mobile detection system. United States: N. p., 2015. Web. doi:10.1016/j.nima.2014.10.045.
Iyengar, Anagha, Beach, Matthew, Newby, Robert J., Fabris, Lorenzo, Heilbronn, Lawrence H., & Hayward, Jason P. Systematic measurement of fast neutron background fluctuations in an urban area using a mobile detection system. United States. https://doi.org/10.1016/j.nima.2014.10.045
Iyengar, Anagha, Beach, Matthew, Newby, Robert J., Fabris, Lorenzo, Heilbronn, Lawrence H., and Hayward, Jason P. Thu . "Systematic measurement of fast neutron background fluctuations in an urban area using a mobile detection system". United States. https://doi.org/10.1016/j.nima.2014.10.045. https://www.osti.gov/servlets/purl/1162069.
@article{osti_1162069,
title = {Systematic measurement of fast neutron background fluctuations in an urban area using a mobile detection system},
author = {Iyengar, Anagha and Beach, Matthew and Newby, Robert J. and Fabris, Lorenzo and Heilbronn, Lawrence H. and Hayward, Jason P.},
abstractNote = {Neutron background measurements using a mobile trailer-based system were conducted in Knoxville, Tennessee. The 0.5 m2 system consisting of 8 EJ-301 liquid scintillation detectors was used to collect neutron background measurements in order to better understand the systematic background variations that depend solely on the street-level measurement position in a local, downtown area. Data was collected along 5 different streets in the downtown Knoxville area, and the measurements were found to be repeatable. Using 10-min measurements, fractional uncertainty in each measured data point was <2%. Compared with fast neutron background count rates measured away from downtown Knoxville, a reduction in background count rates ranging from 10-50% was observed in the downtown area, sometimes varying substantially over distances of tens of meters. These reductions are attributed to the shielding of adjacent buildings, quantified in part here by the metric angle-of-open-sky. The adjacent buildings may serve to shield cosmic ray neutron flux.},
doi = {10.1016/j.nima.2014.10.045},
journal = {Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment},
number = ,
volume = 773,
place = {United States},
year = {Thu Nov 12 00:00:00 EST 2015},
month = {Thu Nov 12 00:00:00 EST 2015}
}

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Works referenced in this record:

Terrestrial cosmic rays
journal, January 1996

  • Ziegler, J. F.
  • IBM Journal of Research and Development, Vol. 40, Issue 1
  • DOI: 10.1147/rd.401.0019

Passive neutron detection for interdiction of nuclear material at borders
journal, January 2008

  • Kouzes, Richard T.; Siciliano, Edward R.; Ely, James H.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 584, Issue 2-3
  • DOI: 10.1016/j.nima.2007.10.026

Altitude Variation of Cosmic-ray Neutrons
journal, January 1987


Study of the Radiation Environment Caused by Galactic Cosmic Rays at Flight Altitudes, at the Summit of the Zugspitze and at PTB Braunschweig
journal, July 1999


Calculation of Radiation Fields in the Atmosphere and Comparison to Experimental Data
journal, January 1998

  • Roesler, S.; Heinrich, W.; Schraube, H.
  • Radiation Research, Vol. 149, Issue 1
  • DOI: 10.2307/3579685

Measurement of the flux and energy spectrum of cosmic-ray induced neutrons on the ground
journal, December 2004

  • Gordon, M. S.; Goldhagen, P.; Rodbell, K. P.
  • IEEE Transactions on Nuclear Science, Vol. 51, Issue 6
  • DOI: 10.1109/TNS.2004.839134

Cosmic ray induced neutron background sources and fluxes for geometries of air over water, ground, iron, and aluminum
journal, January 1978

  • O'Brien, K.; Sandmeier, H. A.; Hansen, G. E.
  • Journal of Geophysical Research: Space Physics, Vol. 83, Issue A1
  • DOI: 10.1029/JA083iA01p00114

Cosmic-ray-induced ship-effect neutron measurements and implications for cargo scanning at borders
journal, March 2008

  • Kouzes, Richard T.; Ely, James H.; Seifert, Allen
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 587, Issue 1, p. 89-100
  • DOI: 10.1016/j.nima.2007.12.031

A study of the cosmic-ray neutron field near interfaces
journal, January 2002

  • Sheu, R. J.; Lin, J. S.; Jiang, S. H.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 476, Issue 1-2
  • DOI: 10.1016/S0168-9002(01)01395-X