Nuclear Engineering and Technology

  • 제56권2호
  • /
  • Pages.753-761
  • /
  • 2024
  • /
  • 1738-5733(pISSN)
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  • 2234-358X(eISSN)
한국원자력학회 (Korean Nuclear Society)
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Neutron dosimetry with a pair of TLDs for the Elekta Precise medical linac and the evaluation of optimum moderator thickness for the conversion of fast to thermal neutrons

  • Marziyeh Behmadi (Cancer Research Center, Semnan University of Medical Sciences) ;
  • Sara Mohammadi (Medical Physics Department, Gonabad University of Medical Sciences) ;
  • Mohammad Ehsan Ravari (Medical Physics Department, Faculty of Medicine, Semnan University of Medical Sciences) ;
  • Aghil Mohammadi (Energy Engineering and Physics Department, Amir Kabir University of Technology) ;
  • Mahdy Ebrahimi Loushab (Department of Physics, Faculty of Shahid Rajaee, Quchan Branch, Technical and Vocational University (TVU)) ;
  • Mohammad Taghi Bahreyni Toossi (Medical Physics Research Center, Mashhad University of Medical Sciences) ;
  • Mitra Ghergherehchi (Department of Electrical and Computer Engineering, Sungkyunkwan University)
  • 투고 : 2022.10.07
  • 심사 : 2023.11.07
  • 발행 : 2024.02.25
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초록

Introduction: In this study, TLD 600 and TLD 700 pairs were used to measure the neutron dose of Elekta Precise medical linac. To this end, the optimum moderate thickness for the conversion of fast to thermal neutrons were evaluated. Materials and methods: 241Am-Be and 252Cf sources were simulated to calculate the optimum thicknesses of the moderator for the conversion of maximum fast neutrons (FN) into thermal neutrons (TN). Pair TLDs were used to measure F&TN doses for three different field sizes at four depths of the medical linac. Results: The maximum thickness of the moderator was optimized at 6 cm. The measurement results demonstrated that the TN dose increased with the expansion of field size and depth. The FN dose, which was converted TN, exhibits behaviors comparable to the TN due to its nature. Conclusion: This study presents the optimum thickness for the moderator to convert FN into TN and measure F&TN using TLDs.

키워드

과제정보

The authors would like to thank the Student Research Committee of Mashhad University of Medical Sciences for the financial support of this research. We are also thankful to the Medical Physics Research Center of Mashhad University of Medical Sciences and Radiation Therapy Department of Emam Reza Hospital for providing technical facilities. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (No. RS-2023-00221186).

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