Journal of radiological science and technology (대한방사선기술학회지:방사선기술과학)

Korean Society of Radiological Science (대한방사선과학회)
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Characterization of the Neutron for Linear Accelerator Shielding Wall using a Monte Carlo Simulation

몬테칼로시뮬레이션을 이용한 선형가속기 차폐벽에 대한 중성자 특성 평가

  • Lee, Dong Yeon (Dept. of Radiation Oncology, Dongnam Inst. of Radiological & Medical Scienc) ;
  • Park, Eun Tae (Dept. of Radiation Oncology, Inje University Busan Paik Hospital) ;
  • Kim, Jung Hoon (Dept. of Radiologic Science, College of Health Sciences, Catholic University of Pusan)
  • 이동연 (동남권원자력의학원 방사선종양학과) ;
  • 박은태 (인제대학교 부산백병원 방사선종양학과) ;
  • 김정훈 (부산가톨릭대학교 보건과학대학 방사선학과)
  • Received : 2016.01.18
  • Accepted : 2016.03.15
  • Published : 2016.03.31
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Abstract

As previous studies to proceed with the evaluation of the radioactive at linear accelerator's shielding concrete wall. And the shielding wall was evaluated the characteristics for the incoming neutron. As a result, the shielding wall is the average amount of incoming neutrons 10 MV 4.63E-7%, 15 MV 9.69E-6%, showed the occurrence of 20 MV 2.18E-5%. The proportion of thermal neutrons of which are found to be approximately 18-33%. The neutron generation rate can be seen as a slight numerical order. However, in consideration of the linear accelerator operating time we can not ignore the effects of neutrons. Accordingly radioactive problem of the radiation shield wall of the treatment room will be this should be considered.

선형가속기를 차폐하고 있는 콘크리트 차폐벽의 방사화 평가를 진행하기 위한 선행 연구로서 차폐벽이 받는 중 성자에 대한 특성을 평가하였다. 그 결과 차폐벽이 받는 중성자 평균 양은 생성된 광자 대비 10 MV 4.63E-7%, 15 MV 9.69E-6%, 20 MV 2.18E-5%의 발생비율을 보였으며, 이 중 반응단면적이 큰 열중성자의 비율은 대략 18 ~ 33%로 나타났다. 의료용 선형가속기의 경우 수년간 지속적으로 가동되기 때문에 중성자 생성 비율에 관계없이 누적으로 생성되는 중성자의 양은 무시할 수 없을 것이며, 이에 따른 방사선 치료실 차폐벽의 방사화 문제는 반드시 고려되어야 할 것이다.

Keywords

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