A matrixinversion method for gammasource mapping from gammacount data
Abstract
In a previous paper it was proposed that a simple matrix inversion method could be used to extract source distributions from gammacount maps, using simple models to calculate the response matrix. The method was tested using numerically generated count maps. In the present work a 100 kBq Co{sup 60} source has been placed on a gridded surface and the count rate measured using a NaI scintillation detector. The resulting map of gamma counts was used as input to the matrix inversion procedure and the source position recovered. A multisource array was simulated by superposition of several singlesource count maps and the source distribution was again recovered using matrix inversion. The measurements were performed for several detector heights. The effects of uncertainties in sourcedetector distances on the matrix inversion method are also examined. The results from this work give confidence in the application of the method to practical applications, such as the segregation of highly active objects amongst fuelelement debris. (authors)
 Authors:
 Consultancy, Nuvia Limited, Harwell Science and Innovation Campus, Didcot, Oxon., OX11 0RL (United Kingdom)
 Department of Materials, Imperial College London, London SW7 2AZ (United Kingdom)
 Health Physics Division, Nuvia Limited, Harwell Science and Innovation Campus, Didcot, Oxon., OX11 0TQ (United Kingdom)
 Publication Date:
 Research Org.:
 American Society of Mechanical Engineers  ASME, Nuclear Engineering Division, Environmental Engineering Division, Two Park Avenue, New York, NY 100165990 (United States)
 OSTI Identifier:
 22535230
 Resource Type:
 Conference
 Resource Relation:
 Conference: ICEM2013  ASME 2013: 15. International Conference on Environmental Remediation and Radioactive Waste Management, Brussels (Belgium), 812 Sep 2013; Other Information: Country of input: France; 3 refs
 Country of Publication:
 United States
 Language:
 English
 Subject:
 97 MATHEMATICAL METHODS AND COMPUTING; 12 MANAGEMENT OF RADIOACTIVE WASTES, AND NONRADIOACTIVE WASTES FROM NUCLEAR FACILITIES; COBALT 60; GAMMA SOURCES; MAPS; MATRICES; NAI DETECTORS; SPENT FUELS
Citation Formats
Adsley, Ian, Burgess, Claire, and Bull, Richard K. A matrixinversion method for gammasource mapping from gammacount data. United States: N. p., 2013.
Web. doi:10.1115/ICEM201396017.
Adsley, Ian, Burgess, Claire, & Bull, Richard K. A matrixinversion method for gammasource mapping from gammacount data. United States. doi:10.1115/ICEM201396017.
Adsley, Ian, Burgess, Claire, and Bull, Richard K. 2013.
"A matrixinversion method for gammasource mapping from gammacount data". United States.
doi:10.1115/ICEM201396017.
@article{osti_22535230,
title = {A matrixinversion method for gammasource mapping from gammacount data},
author = {Adsley, Ian and Burgess, Claire and Bull, Richard K},
abstractNote = {In a previous paper it was proposed that a simple matrix inversion method could be used to extract source distributions from gammacount maps, using simple models to calculate the response matrix. The method was tested using numerically generated count maps. In the present work a 100 kBq Co{sup 60} source has been placed on a gridded surface and the count rate measured using a NaI scintillation detector. The resulting map of gamma counts was used as input to the matrix inversion procedure and the source position recovered. A multisource array was simulated by superposition of several singlesource count maps and the source distribution was again recovered using matrix inversion. The measurements were performed for several detector heights. The effects of uncertainties in sourcedetector distances on the matrix inversion method are also examined. The results from this work give confidence in the application of the method to practical applications, such as the segregation of highly active objects amongst fuelelement debris. (authors)},
doi = {10.1115/ICEM201396017},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2013,
month = 7
}

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