Turkish Journal of Nuclear Sciences 2791-7185 T.C. Türkiye Enerji, Nükleer ve Maden Araştırma Kurumu Metrology, Applied and Industrial Physics Metroloji,Uygulamalı ve Endüstriyel Fizik EFFECT OF SAMPLE POSITION ON EFFICIENCY IN GAMMA-RAY SPECTROSCOPY Uyar Esra GAZİ ÜNİVERSİTESİ, FEN FAKÜLTESİ https://orcid.org/0000-0002-2197-2429 Özgür Mine Türkiye Enerji, Nükleer ve Maden Araştırma Kurumu, Nükleer Enerji Araştırma Enstitüsü https://orcid.org/0000-0002-3705-4315 Dikmen Hasan Türkiye Enerji, Nükleer ve Maden Araştırma Kurumu, Nükleer Enerji Araştırma Enstitüsü 12 30 2023 36 2 14 20 09 21 2023 12 29 2023 Copyright © 1981, Turkish Journal of Nuclear Sciences 1981 Turkish Journal of Nuclear Sciences

The full energy peak efficiency for the energies of interest must be known to determine the concentration of activity in gamma-ray spectrometry. This work is focused on examining the effect of sample position on full energy peak efficiency. For this purpose, efficiency values were determined by experimental and Monte Carlo simulation method using three different HPGe detectors and standard charcoal cartridges. The cartridges were first counted in the centers of the detectors and then replaced on the X-axis at 5 mm intervals. At maximum distances from the center of 25 mm for Ge-1, 15 mm for Ge-2, and 10 mm for Ge-3, experimental full energy peak values are 11.8-16.4% in Ge-1, 8.2-13.8% in Ge-2, and decrease between 4.9-11.0% in Ge-3. The results show that the sample position significantly affects the full energy peak efficiency, using a sample locator if possible, if not counting as carefully in the center as possible.

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