The Treatment of Efficiency of NaI(Tl) Detector By Using Monte Carlo Simulation

Abstract

An efficient Monte Carlo computer program for simulation and calculation of the total and full energy peak efficiency (absolute and intrinsic) of the cylindrical NaI(Tl)detector (with different : volumes, source-detector separation and gamma rays energies) is described. All the fundamental physical processes (photoelectric effect, compton scattering effect and pair production effect) occurring inside the detector are taken into account. Very fast analytical expressions for the absorption coefficients are obtained. The same program can be used to calculate the response function of the detector to gamma ray. The results show quite well agreement with experimental data and with other calculations within error rate less than 2%. The results can be used in gamma spectroscopy and determining the activity of sources. ‫ﻜﺎﺸﻑ‬ ‫ﻜﻔﺎﺀﺓ‬ ‫ﻤﻌﺎﻟﺠﺔ‬ NaI(Tl) ‫ﺒ‬ ‫ﺈ‬  ‫ﻤﻭﻨﺕ‬ ‫ﻤﺤﺎﻜﺎﺓ‬ ‫ﺴﺘﺨﺩﺍﻡ‬ ‫ﻜﺎﺭﻟﻭ‬ ‫ﺍﻟﺨﻼﺼﺔ‬ ‫ﻤﻭﻨ‬ ‫ﻁﺭﻴﻘﺔ‬ ‫ﻴﻌﺘﻤﺩ‬ ‫ﺒﺭﻨﺎﻤﺞ‬ ‫ﺘﺼﻤﻴﻡ‬ ‫ﺘﻡ‬ ‫ﺍﻟﻜﻠﻴﺔ‬ ‫ﺍﻟﻜﻔﺎﺀﺓ‬ ‫ﻭﺤﺴﺎﺏ‬ ‫ﻤﺤﺎﻜﺎﺓ‬ ‫ﻓﻲ‬ ‫ﻜﻔﻭﺀ‬ ،‫ﻜﺎﺭﻟﻭ‬  ‫ﺕ‬ ‫ﻭﻜﻔﺎﺀﺓ‬ ‫ﺍ‬ ‫ﻹ‬ ‫ﺍﻟﻜﻠﻲ‬ ‫ﻤﺘﺼﺎﺹ‬) ‫ﻭﺍﻟﺫﺍﺘﻴﺔ‬ ‫ﺍﻟﻤﻁﻠﻘﺔ‬ (‫ﻟﻜﺎﺸﻑ‬ NaI(Tl) ‫ﺍﻹﺴﻁﻭﺍﻨﻲ‬) ‫ﺍﻟﻤﺼﺩﺭ‬ ‫ﺒﻴﻥ‬ ‫ﻭﻤﺴﺎﻓﺎﺕ‬ ‫ﺒﺤﺠﻭﻡ‬ ‫ﻭﺍﻟﻜﺎﺸﻑ‬ ‫ﺃﺸﻌﺔ‬ ‫ﻭﻁﺎﻗﺎﺕ‬ ‫ﮔ‬ ‫ﻤﺨﺘﻠﻔﺔ‬ ، ‫ﺍﻤﺎ‬. (‫ﺃ‬ ‫ﻟﻘﺩ‬ ‫ۥ‬ ‫ﺫﺕ‬ ‫ﺨ‬˚‫ﺍ‬ ‫ﺨ‬˚ ‫ﺨ‬˚‫ﺍ‬ ‫ﺒﻨﻅﺭ‬ ‫ﻹ‬ ‫ﺍﻟﻔﻴﺯﻴﺎﺌﻴﺔ‬ ‫ﺍﻟﻌﻤﻠﻴﺎﺕ‬ ‫ﺠﻤﻴﻊ‬ ‫ﻋﺘﺒﺎﺭ‬ ‫ﺍﻟﺭﺌﻴﺴﺔ‬) ‫ﻭﺘﺄﺜ‬ ‫ﺍﻟﻜﻬﺭﻭﻀﻭﺌﻲ‬ ‫ﺍﻟﺜﺄﺜﻴﺭ‬ ‫ﻴﺭ‬ ‫ٳ‬ ‫ﻭﺘﺄﺜﻴﺭ‬ ‫ﻜﻭﻤﺒﺘﻥ‬ ‫ﺴﺘﻁﺎﺭﺓ‬ ‫ٳ‬ ‫ﺍﻟﺯﻭﺝ‬ ‫ﻨﺘﺎﺝ‬ (‫ﺍﻟﻜﺎﺸﻑ‬ ‫ﻓﻲ‬ ‫ﺘﺤﺩﺙ‬ ‫ﺍﻟﺘﻲ‬ ‫ﺃﺸﻌﺔ‬ ‫ﺘﻔﺎﻋل‬ ‫ﻋﻨﺩ‬ ‫ﮔ‬ ‫ﻤﻌﻪ‬ ‫ﺍﻤﺎ‬. ‫ﺍ‬ ‫ﻤﻌﺎﻤﻼﺕ‬ ‫ﻤﻭﺍﺌﻤﺔ‬ ‫ﺘﻡ‬ ‫ﻓﻘﺩ‬ ، ‫ﺍﻟﺒﺭﻨﺎﻤﺞ‬ ‫ﻓﺎﻋﻠﻴﺔ‬ ‫ﻭﻟﺯﻴﺎﺩﺓ‬ ‫ﻹ‬ ‫ﻷﺸﻌﺔ‬ ‫ﻤﺘﺼﺎﺹ‬ ‫ﮔ‬ ‫ﺍﻤﺎ‬ ‫ﻟﻠﻁﺎﻗﺔ‬ ‫ﻜﺩﺍﻟﺔ‬ ‫ﺭﻴﺎﻀﻴﺔ‬ ‫ﺒﺘﻌﺎﺒﻴﺭ‬ ‫ﺍﻟﻜﺎﺸﻑ‬ ‫ﻤﺎﺩﺓ‬ ‫ﻓﻲ‬. ‫ﺃﻴﻀﺎ‬ ‫ﺍﻟﻤﻤﻜﻥ‬ ‫ﻭﻤﻥ‬ ˝ ‫ٳ‬ ‫ﺩﺍﻟﺔ‬ ‫ﻟﺤﺴﺎﺏ‬ ‫ﺍﻟﺒﺭﻨﺎﻤﺞ‬ ‫ﺴﺘﺨﺩﺍﻡ‬ ‫ﺍ‬ ‫ﻹ‬ ‫ﻷ‬ ‫ﻟﻠﻜﺎﺸﻑ‬ ‫ﺴﺘﺠﺎﺒﺔ‬ ‫ﺸﻌﺔ‬ ‫ﮔ‬ ‫ﺍﻤﺎ‬. ‫ﻭﺍﻟﺤﺴﺎﺒﺎﺕ‬ ‫ﺍﻟﻌﻤﻠﻴﺔ‬ ‫ﺍﻟﻘﻴﺎﺴﺎﺕ‬ ‫ﻤﻊ‬ ‫ﻋﺎﻟﻲ‬ ‫ﺘﻭﺍﻓﻕ‬ ‫ﺍﻟﻨﺘﺎﺌﺞ‬ ‫ﺃﻅﻬﺭﺕ‬ ‫ﻟﻘﺩ‬ ‫ﺍﻷ‬ ‫ﺍﻟﻨﻅﺭﻴﺔ‬ ‫ۥ‬ ‫ﻻﺘﺘﺠﺎﻭﺯ‬ ‫ﺨﻁﺄ‬ ‫ﺒﻨﺴﺒﺔ‬ ‫ﺨﺭﻯ‬ 2 .% ‫ﺍﻟﻤﻤﻜﻥ‬ ‫ﻤﻥ‬ ‫ٳ‬ ‫ﺃﺸﻌﺔ‬ ‫ﻁﻴﻑ‬ ‫ﻗﻴﺎﺴﺎﺕ‬ ‫ﻓﻲ‬ ‫ﺍﻟﻨﺘﺎﺌﺞ‬ ‫ﺴﺘﺨﺩﺍﻡ‬ ‫ﮔ‬ ‫ﺍﻟ‬ ‫ﻓﻌﺎﻟﻴﺔ‬ ‫ﻭﺤﺴﺎﺏ‬ ‫ﺍﻤﺎ‬ ‫ﻤ‬ ‫ﺍﻟﻤﺸﻌﺔ‬ ‫ﺼﺎﺩﺭ‬. https://doi.org/10.30684/etj.28.5.12 2412-0758/University of Technology-Iraq, Baghdad, Iraq This is an open access article under the CC BY 4.0 license http://creativecommons.org/licenses/by/4.0