Progress in Medical Physics (한국의학물리학회지:의학물리)

Korean Society of Medical Physics (한국의학물리학회)
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Calculation of Energy Spectra for Electron Beam of Medical Linear Accelerator Using GEANT4

GEANT4를 이용한 선형가속기 기초 코드 작성과 전자선 에너지 분포 계산

  • Joh, Young-Gull (Department of Physics, College of Science, Yeungnam University) ;
  • Kim, Hyung-Dong (Department of Physics, College of Science, Yeungnam University) ;
  • Kim, Byung-Young (Department of Physics, College of Science, Yeungnam University) ;
  • Kim, Sung-Jin (Department of Physics, College of Science, Yeungnam University) ;
  • Oh, Se-An (Department of Physics, College of Science, Yeungnam University) ;
  • Kang, Jeong-Ku (Department of Radiation Oncology, Prebysterian Medical Center) ;
  • Kim, Sung-Kyu (Department of Therapeutic Radiology&Oncology, College of Medicine, Yeungnam University)
  • 조영걸 (영남대학교 이과대학 물리학과) ;
  • 김형동 (영남대학교 이과대학 물리학과) ;
  • 김병용 (영남대학교 이과대학 물리학과) ;
  • 김성진 (영남대학교 이과대학 물리학과) ;
  • 오세안 (영남대학교 이과대학 물리학과) ;
  • 강정구 (전주예수병원 방사선종양학과) ;
  • 김성규 (영남대학교 의과대학 방사선종양학교실)
  • Received : 2011.05.16
  • Accepted : 2011.06.30
  • Published : 2011.06.30
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Abstract

The energy spectra for electron beam of medical linear accelerator were calculated using a GEANT4 Medical Linac 2 example code. The incident electron mean energy were 6, 9, 12, 16, 20 MeV. This code was designed to calculate electron beam energy spectra according to material, thickness and location of electron scattering foil affecting electron beam characteristic. Lead, Copper, Aluminum and Gold were used for scattering foil. The energy distribution for electron and photon were analyzed by changing position of scattering foil in the head of linear accelerator. The effect of electron scattering foil on energy spectra which is basic data of simulation for medical linear accelerator were presented. The calculated results would be used in design of medical accelerator head.

GEANT4 Medical Linac 2 예제 코드를 이용하여 선형가속기 전자선의 에너지 분포를 계산하였다. 입사 전자의 평균 에너지는 6, 9, 12, 16, 20 MeV이었으며, 전자선 특성에 영향을 주는 전자선 산란박 물질, 두께, 위치에 따른 에너지 분포를 계산하였다. 산란박 물질은 납, 구리, 알루미늄, 금을 사용하였다. 산란박 위치를 변경하여 선형 가속기 헤드 속 산란박 위치가 전자 및 광자 에너지 분포에 미치는 영향을 분석하였다. 의료용 선형가속기 시뮬레이션의 기초자료인 에너지 분포에 대해 여러 가지 산란박 조건을 적용하여 경향을 나타내었다. 이 결과는 선형가속기 헤드 설계에 이용될 수 있을 것으로 본다.

Keywords

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