Calculation of self-absorption and coincidence summing correction factors for the extended sources using GEANT4

2019 ◽  
Vol 54 (2) ◽  
pp. 133-140
Author(s):  
W. Khan ◽  
C. He ◽  
Y. Cao
Keyword(s):  
Full Energy Peak ◽  
Experimental Results ◽  
Correction Factors ◽  
Peak Efficiency ◽  
Full Energy ◽  
Water Composition ◽  
Absorption Correction ◽  
Energy Peak ◽  
Full Energy Peak Efficiency ◽  
Coincidence Summing

A detailed study of the full energy peak efficiency of a high purity germanium (HPGe) detector including the effect of source self-absorption and coincidence summing was performed using Monte Carlo simulation, as it is difficult and time-consuming to measure the full energy peak efficiency experimentally. Cylindrical water composition source was simulated with different characteristics, covering the energy range from 60 to 1836 keV. Self-absorption correction factors (SAFcal) were calculated for two source volumes and obtained good agreement with the experimental results except for (60Co and 88Y) nuclides. The simulation was performed for various samples with different densities and observed their effects on the full energy peak efficiency value of the detector. In the case of extended volumetric source, the coincidence summing correction factors (CSFcal) for two nuclides (60Co and 88Y) were estimated with the GEANT4 simulation toolkit. The effect of correction factors on different cylindrical source volumes was also investigated. With the self-absorption and coincidence summing effect, the best agreement was achieved between simulated and experimental results with discrepancy less than 2% for all of the radionuclides included in two source volumes.

Calibration of HPGe Detector Efficiencies With Self-Absorption Correction of Gas Sphere Sources

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Waseem Khan ◽  
Chaohui He
Keyword(s):  
Point Sources ◽  
Full Energy Peak ◽  
Wall Material ◽  
Correction Factors ◽  
Peak Efficiency ◽  
Good Efficiency ◽  
Full Energy ◽  
Absorption Correction ◽  
Energy Peak ◽  
Full Energy Peak Efficiency

Several types of radioactive gases are released from the nuclear reactor. In order to measure the activity of such gases, it is necessary to calculate the accurate efficiency. Practically, efficiency calibration with gaseous sources is not very easy because of the low half-lives of the noble gases. For this purpose, Monte Carlo (MC) simulation was performed to study the full energy peak efficiency of two n-type high-purity Germanium (HPGe) detectors. Two spheres of xenon and krypton composition sources with two nuclides (Xe133 and Kr85) and two-point sources were simulated, covering the energy range from 81 keV to 604 keV. Self-absorption correction factors were calculated with GEANT4 for two gas sphere samples and obtained good efficiency agreement with the experimental results. The simulation was performed for various gas samples with different densities and observed their effects on the full energy peak efficiency value of two detectors. The corresponding self-absorption correction factors were calculated for each gaseous sample and investigated that the self-absorption correction factors not only depend on the sample characteristics but also on the detector geometry and source to detector distance. The dependence of the full energy peak efficiency on the side cap wall material and their thicknesses were also carried out for some particular photon energies.

Full-Energy peak efficiency of an NaI(Tl) detector with coincidence summing correction showing the effect of the source-to-detector distance

2017 ◽  
Vol 55 (2) ◽  
pp. 478-489 ◽  
Author(s):  
Ahmed M. El-Khatib ◽  
Bohaysa A. Salem ◽  
Mohamed S. Badawi ◽  
Mona M. Gouda ◽  
Abouzeid A. Thabet ◽  
...  
Keyword(s):  
Full Energy Peak ◽  
Peak Efficiency ◽  
Full Energy ◽  
Detector Distance ◽  
Energy Peak ◽  
Full Energy Peak Efficiency ◽  
Coincidence Summing

scholarly journals Progress in radionuclide characterisation in marine sediments using an underwater gamma-ray spectrometer in 2π geometry

2019 ◽  
Vol 21 ◽  
pp. 29
Author(s):  
E. G. Androulakaki ◽  
C. Tsabaris ◽  
M. Kokkoris ◽  
G. Eleftheriou ◽  
D. L. Patiris ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Detection System ◽  
Full Energy Peak ◽  
Gamma Ray Spectrometry ◽  
Peak Efficiency ◽  
Full Energy ◽  
Effective Manner ◽  
Energy Peak ◽  
Full Energy Peak Efficiency

The in-situ gamma-ray spectrometry is a well suited method for seabed mapping applications, since it provides rapid results in a cost effective manner. Moreover, the in-situ method is preferable to the commonly applied laboratory measurements, due to its beneficial characteristics. Therefore, the development of in-situ systems for seabed measurements continuously grows. However, an efficiency calibration of the detection system is necessary for obtaining quantitative results in the full spectral range. In the present work, an approach for calculating the full-energy peak efficiency of an underwater insitu spectrometer for measure- ments on the seabed is presented. The experimental work was performed at the coastal site of Vasilikos (Cyprus). The experimental full-energy peak efficiency of the in-situ was determined in the energy range 1400–2600 keV, by combining the in-situ and laboratory reference measurements. The experimental effi- ciency results were theoretically reproduced by means of Monte Carlo (MC) simulations, using the MCNP5 code.

Sign in / Sign up

Export Citation Format

Share Document