Journal of the Korean Society of Radiology (한국방사선학회논문지)

The Korean Society of Radiology (한국방사선학회)
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A Study of Targetry Activation and Dose Analysis of PET Cyclotron Using Monte Carlo Simulation

몬테카를로 모의 모사를 이용한 의료용 사이클로트론의 Targetry 방사화 및 피폭선량 분석

  • Jang, Donggun (Department of Nuclear Medicine, Dongnam Institute of Radiological & Medical Sciences Cancer center) ;
  • Kim, Dong hyun (Department of Radiological Science, College of Health Sciences, Catholic University of Pusan)
  • 장동근 (동남권 원자력의학원 핵의학과) ;
  • 김동현 (부산가톨릭대학교 보건과학대학 방사선학과)
  • Received : 2018.06.12
  • Accepted : 2018.10.31
  • Published : 2018.10.31
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Abstract

Cyclotron for medical purposes generates nuclear reaction by accelerating protons in high speed, in order to produce radiopharmaceuticals, and unnecessary neutrons are generated through such nuclear reaction. Neutrons cause activation in the parts of cyclotron which then cause exposure to radiation for people working in the field. This study, in that regard, aims to analyze exposure level by finding out the degree of activation of aluminum body, silver body, and havar foil which are the parts of Targetry where the nuclear reaction takes place. The results of the experiment showed that aluminum body and silver body had no problems re-using them as the energy and half-life of activated nuclides were small and short, making the affect on the people working in the field extremely low. However for havar foil, its activated nuclides had a high level of energy which resulted in high level of affect to the people working in the field. The activation factors of the cyclotron were analyzed, and the results showed that the Havar foil was activated the most among the targetry parts, and greatly exposed workers due to regular replacement, and needed special management as radioactive waste.

의료용 사이크로트론은 방사성의약품을 생산하기 위해 양성자를 고속으로 가속시켜 핵반응을 일으키게 되며, 핵반응을 통해 불필요한 중성자가 발생하게 된다. 중성자는 사이클로트론의 부품에 방사화를 일으키는 원인으로 종사자들의 피폭의 원인이 된다. 이에 본 연구에서는 핵반응이 일어나는 Targetry 부품들인 Aluminum body, Silver body, Havar foil의 방사화 정도를 분석하여 피폭선량을 알아보고자 하였다. 실험결과 Aluminum body와 Silver body는 방사화된 핵종들의 에너지가 작고, 반감기가 짧아 종사들에게 미치는 선량이 미미하였으며, 재사용하는데 문제가 없었다. 하지만 Havar foil의 경우 방사화된 핵종들의 에너지가 높고 반감기가 길어 종사자들에게 미치는 영향이 매우 높았으며, 방사성폐기물로써 특별한 관리가 필용한 것으로 나타났다.

Keywords

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