Development of an optimized Compton suppression gamma-ray spectrometric system using Monte Carlo simulation. (March 2016)

• Record Type: Journal Article
• Authors: Choi, Y.; Lee, K.B.; Kim, K.J.; Han, J.; Yi, E.S.
• Is Part Of: Applied radiation and isotopes. Volume 109(2016:Mar.)
• Page Start: 558
• Page End: 562
• Publication Date: 2016-03
• Subjects: Compton Suppression System -- Compton Suppression Factor -- Monte Carlo simulation -- PENELOPE -- Timing resolution; Radiology -- Periodicals; Radiation -- Industrial applications -- Periodicals; Nuclear chemistry -- Periodicals; Internet resource; Periodical; 660.298
• DOI: 10.1016/j.apradiso.2015.12.058
• Languages: English
• ISSNs: 0969-8043

Abstract

Abstract: We have chosen to establish the Compton Suppression Spectrometer (CSS) for low activity environmental samples with a high purity germanium (HPGe) primary detector and a removable plug-in detector (NaI(Tl)) surrounded with a cylindrical annulus guard detector (NaI(Tl)). Monte Carlo simulation with PENELOPE (PENetration and Energy LOss of Positrons and Electrons) is used to determine the optimal geometry of the CSS. To verify a correlation between experiment and simulation, the energy distribution of 137 Cs and 60 Co point sources is measured and simulated for each condition. The CSS parameters are studied to determine optimal detector geometry and Compton Suppression Factor (CSF). The timing resolution of the CSS was found to be 44 ns (FWHM), which is an outstanding result in the semiconductor-based gamma-ray spectrometry. All measured values of CSF agree within 5% with the values obtained from the simulation. The optimum geometry and CSF values are discussed. Highlights: The CSS was evaluated by Compton Suppression Factor (CSF), P/C and P/T ratio. Timing resolution of the CSS is 44 ns (FWHM), which is an outstanding result. All measured values of CSF agree within 5% with the results of simulations. The optimal experimental value of the CSF is 6.89±0.14. It is obtained with the point source at 36% of the height of the annulus NaI(Tl).