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Title: Validation of the intrinsic spatial efficiency method for non cylindrical homogeneous sources using MC simulation

Abstract

The Monte Carlo simulation of the gamma spectroscopy systems is a common practice in these days. The most popular softwares to do this are MCNP and Geant4 codes. The intrinsic spatial efficiency method is a general and absolute method to determine the absolute efficiency of a spectroscopy system for any extended sources, but this was only demonstrated experimentally for cylindrical sources. Due to the difficulty that the preparation of sources with any shape represents, the simplest way to do this is by the simulation of the spectroscopy system and the source. In this work we present the validation of the intrinsic spatial efficiency method for sources with different geometries and for photons with an energy of 661.65 keV. In the simulation the matrix effects (the auto-attenuation effect) are not considered, therefore these results are only preliminaries. The MC simulation is carried out using the FLUKA code and the absolute efficiency of the detector is determined using two methods: the statistical count of Full Energy Peak (FEP) area (traditional method) and the intrinsic spatial efficiency method. The obtained results show total agreement between the absolute efficiencies determined by the traditional method and the intrinsic spatial efficiency method. The relative bias ismore » lesser than 1% in all cases.« less

Authors:
;  [1]
  1. Departamento de Física, Facultad de Ciencias, Universidad de Chile (Chile)
Publication Date:
OSTI Identifier:
22608520
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1753; Journal Issue: 1; Conference: Latin American symposium on nuclear physics and applications, Medellin (Colombia), 30 Nov - 4 Dec 2015; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ATTENUATION; COMPUTERIZED SIMULATION; CYLINDRICAL CONFIGURATION; EFFICIENCY; GAMMA SPECTROSCOPY; KEV RANGE; MONTE CARLO METHOD; PHOTONS

Citation Formats

Ortiz-Ramírez, Pablo, E-mail: rapeitor@ug.uchile.cl, and Ruiz, Andrés. Validation of the intrinsic spatial efficiency method for non cylindrical homogeneous sources using MC simulation. United States: N. p., 2016. Web. doi:10.1063/1.4955373.
Ortiz-Ramírez, Pablo, E-mail: rapeitor@ug.uchile.cl, & Ruiz, Andrés. Validation of the intrinsic spatial efficiency method for non cylindrical homogeneous sources using MC simulation. United States. doi:10.1063/1.4955373.
Ortiz-Ramírez, Pablo, E-mail: rapeitor@ug.uchile.cl, and Ruiz, Andrés. 2016. "Validation of the intrinsic spatial efficiency method for non cylindrical homogeneous sources using MC simulation". United States. doi:10.1063/1.4955373.
@article{osti_22608520,
title = {Validation of the intrinsic spatial efficiency method for non cylindrical homogeneous sources using MC simulation},
author = {Ortiz-Ramírez, Pablo, E-mail: rapeitor@ug.uchile.cl and Ruiz, Andrés},
abstractNote = {The Monte Carlo simulation of the gamma spectroscopy systems is a common practice in these days. The most popular softwares to do this are MCNP and Geant4 codes. The intrinsic spatial efficiency method is a general and absolute method to determine the absolute efficiency of a spectroscopy system for any extended sources, but this was only demonstrated experimentally for cylindrical sources. Due to the difficulty that the preparation of sources with any shape represents, the simplest way to do this is by the simulation of the spectroscopy system and the source. In this work we present the validation of the intrinsic spatial efficiency method for sources with different geometries and for photons with an energy of 661.65 keV. In the simulation the matrix effects (the auto-attenuation effect) are not considered, therefore these results are only preliminaries. The MC simulation is carried out using the FLUKA code and the absolute efficiency of the detector is determined using two methods: the statistical count of Full Energy Peak (FEP) area (traditional method) and the intrinsic spatial efficiency method. The obtained results show total agreement between the absolute efficiencies determined by the traditional method and the intrinsic spatial efficiency method. The relative bias is lesser than 1% in all cases.},
doi = {10.1063/1.4955373},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1753,
place = {United States},
year = 2016,
month = 7
}
  • The intrinsic spatial efficiency method is a new absolute method to determine the efficiency of a gamma spectroscopy system for any extended source. In the original work the method was experimentally demonstrated and validated for homogeneous cylindrical sources containing {sup 137}Cs, whose sizes varied over a small range (29.5 mm radius and 15.0 to 25.9 mm height). In this work we present an extension of the validation over a wide range of sizes. The dimensions of the cylindrical sources vary between 10 to 40 mm height and 8 to 30 mm radius. The cylindrical sources were prepared using the referencemore » material IAEA-372, which had a specific activity of 11320 Bq/kg at july 2006. The obtained results were better for the sources with 29 mm radius showing relative bias lesser than 5% and for the sources with 10 mm height showing relative bias lesser than 6%. In comparison with the obtained results in the work where we present the method, the majority of these results show an excellent agreement.« less
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