소형 전리함에 대한 TRS-398 선질인자 계산과 중심전극 보정에 관한 연구

Study on the Evaluation of TRS-398 Quality Factors with Central Electrode Corrections for Small Cylindrical Chambers

  • 강영록 (동남권원자력의학원 연구센터) ;
  • 이창열 (동남권원자력의학원 방사선종양학과) ;
  • 김진호 (동남권원자력의학원 방사선종양학과) ;
  • 문영민 (동남권원자력의학원 연구센터) ;
  • 곽동원 (동남권원자력의학원 연구센터) ;
  • 강상구 (전북대학교 방사선과학기술학과) ;
  • 김정기 (동남권원자력의학원 연구센터) ;
  • 양광모 (동남권원자력의학원 연구센터) ;
  • 정동혁 (동남권원자력의학원 연구센터)
  • Kang, Yeong-Rok (Research Center, Dongnam Inst. of Radiological & Medical Sciences) ;
  • Lee, Chang-Yeol (Department of Rad. Oncology, Dongnam Inst. of Radiological & Medical Sciences) ;
  • Kim, Jin-Ho (Department of Rad. Oncology, Dongnam Inst. of Radiological & Medical Sciences) ;
  • Moon, Young-Min (Research Center, Dongnam Inst. of Radiological & Medical Sciences) ;
  • Kwak, Dong-Won (Research Center, Dongnam Inst. of Radiological & Medical Sciences) ;
  • Kang, Sang-Koo (Department of Radiation Science & Technology, Chonbuk National University) ;
  • Kim, Jeung-Kee (Research Center, Dongnam Inst. of Radiological & Medical Sciences) ;
  • Yang, Kwang-Mo (Research Center, Dongnam Inst. of Radiological & Medical Sciences) ;
  • Jeong, Dong-Hyeok (Research Center, Dongnam Inst. of Radiological & Medical Sciences)
  • 투고 : 2011.09.01
  • 심사 : 2011.09.21
  • 발행 : 2011.09.30

초록

TRS-398 프로토콜에서 중심전극에 대한 최근의 연구 결과들을 적용하여 선질인자($k_{Q,Q_0}$)를 평가하였다. 대상 전리함은 PTW-31010과 IBA-CC13이었다. 광자선 및 전자선 선질의 함수로서 선질인자를 계산하였으며 현재 TRS-398 프로토콜의 값들과 비교하였다. PTW-31010 전리함과 같이 알루미늄 전극으로 구성된 전리함에 대하여 새로운 보정을 취하는 경우에 선질인자가 광자선에서 최대 0.4% 그리고 전자선에서 최대 0.9% 증가하는 것으로 나타났다. 또한 IBA-CC13과 같이 C-552 전극을 사용하는 전리함의 경우에 기존의 보정체계를 그대로 적용할 수 있음을 확인하였다.

The quality factors ($k_{Q,Q_0}$) were evaluated by appling the results recently studied for the effect of central electrode in TRS-398 protocol. The PTW-31010 and IBA-CC13 chambers were used in this study. The quality factors were calculated as a function of beam quality for high energy electron and photon beams and compared with data currently used in TRS-398 protocol. In the PTW-31010 chamber using aluminium electrode, appling the new central electrode collections, the quality factors were 0.4% and 0.9% higher than current TRS-398 data for high energy photon and electron beams respectively. In the IBA-CC13 chamber using C-552 electrode, there are no variations in quality factors compared to TRS-398 data currently used.

키워드

참고문헌

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