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Title: GEANT4 investigation of 40K and 222Rn interference effects on actinide detection sensitivities of CEMRC BEGe lung detectors

Journal Article · · Radiation Physics and Chemistry (1993)
 [1];  [2];  [3]
  1. Univ. of Guelph, ON (Canada)
  2. Carlsbad Environmental Monitoring and Research Center, Carlsbad, NM (United States)
  3. The Norm Group, Guelph, ON (Canada)
+ Show Author Affiliations

Internal dosimetry measurements of trans-uranic (TRU) radionuclides within the human body can be accomplished by γ-ray spectroscopy using high-purity germanium detectors. While measurements are typically conducted inside shielded chambers in order to minimize the background detector signal, the presence of radioactive 40K within the body cannot be removed, which produces a high-energy γ ray at 1461 keV. The 40K, in addition to airborne 222Rn, contributes to the radiation field within the chamber that increases to the minimum detectable activity that can be achieved in practice. The objective of the present work is to estimate the contributions from 40K internal to the human body and airborne 222Rn to the background signal in a lung counter germanium detector array using GEANT4 simulations, with a focus on TRU isotope energy region (17–59 keV). The investigations consisted of three main simulations: 1. Simulating the γ-ray flux at the geometric center of the CEMRC counting chamber arising from a 25 nCi source of 40K from (a) a point source, and (b) a source distributed throughout a BOMAB phantom. 2. Simulating the response of the CEMRC BEGe detectors arising from a 25 nCi source of 40K from (a) a point source, and (b) a source distributed throughout a BOMAB phantom. 3. Simulating the response of the CEMRC BEGe detectors to the environmental background in the counting chamber, consisting of airborne 222Rn (0–4 pCi/L) and 40K (0–160 nCi) internal to the human body. The results are used to investigate the 40K background contribution to a routine spectrum recorded by the lung detectors at the CEMRC Internal Dosimetry laboratory over a typical half hour counting interval used in the dosimetry of radiological workers. The minimum detectable activity was calculated for various 222Rn and 40K activities and compared to experimentally determined values. The contribution of cosmic rays was not included in this investigation.

Research Organization:
Carlsbad Environmental Monitoring and Research Center, Carlsbad, NM (United States)
Sponsoring Organization:
USDOE Office of Environmental Management (EM)
Grant/Contract Number:
EM0002423
OSTI ID:
1613254
Journal Information:
Radiation Physics and Chemistry (1993), Vol. 153; ISSN 0969-806X
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 2 works
Citation information provided by
Web of Science

References (11)

Geant4—a simulation toolkit
  • Agostinelli, S.; Allison, J.; Amako, K.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 506, Issue 3 https://doi.org/10.1016/S0168-9002(03)01368-8
journal July 2003
An Evaluation of Germanium Detectors Employed for the Measurement of Radionuclides Deposited in Lungs Using an Experimental and Monte Carlo Approach journal January 2001
An Evaluation of In vivo Sensitivity via Public Monitoring journal July 2000
Assay of actinides in human urine by rapid method journal September 2017
The activity of one gram of potassium journal February 1997
Monte Carlo simulation of the BEGe detector response function for in vivo measurements of 241Am in the skull journal November 2014
The relation of total body potassium to height, weight, and age in normal adults journal June 1972
Basic anatomical and physiological data for use in radiological protection: reference values: ICRP Publication 89: Approved by the Commission in September 2001 journal September 2002
Limits for qualitative detection and quantitative determination. Application to radiochemistry journal March 1968
An Evaluation of Recent Lung Counting Technology journal July 2000
Further considerations for the setting up of a low background whole-body counter for internal dosimetry at Waste Isolation Pilot Plant (WIPP) Carlsbad, NM, USA: transmitted photon component journal September 2014

Figures / Tables (11)

Table 1(p. 2)table Table 1
Figure 1(p. 3)figure Figure 1
Figure 2(p. 3)figure Figure 2
Figure 3(p. 5)figure Figure 3
Figure 4(p. 5)figure Figure 4
Figure 5(p. 5)figure Figure 5
Figure 6(p. 6)figure Figure 6
Figure 7(p. 6)figure Figure 7
Figure 8(p. 7)figure Figure 8
Figure 9(p. 7)figure Figure 9
Table 2(p. 7)table Table 2

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38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
internal dosimetry
germanium detectors
γ-ray spectroscopy
GEANT4