Characteristic analysis of a photon converter in a medical LINAC using GEANT4

Junho Ko1, Beom Yeong Kim2, Yoon Sang Kim3

1, 2, 3School of Computer Science and Engineering, Korea University of Technology and Education, Cheonan, Republic of Korea

3Institute for Bioengineering Application Technology, Korea University of Technology and Education,
Cheonan, Republic of Korea

3Corresponding author

E-mail: 1lich126@koreatech.ac.kr, 2tibyte@koreatech.ac.kr, 3yoonsang@koreatech.ac.kr

Received 12 September 2017; accepted 19 September 2017

DOI https://doi.org/10.21595/vp.2017.19169

 

Abstract. Medical LINACs (Linear Accelerators) use high energy photon beams to treat deeply located tumors. Generally, neutrons are produced by photonuclear reactions in the head of a medical LINAC using photon beams over 8 MV. Neutrons with high relative biological effectiveness and high permeability can cause many problems in terms of radiation protection. The threshold energy of photons producing neutrons in the head of a medical LINAC is 13.06 MV (Aluminum), 13.38 MV (Iron), 8.06 MV (Gold), and 7.41 MV (Tungsten). In this paper, we aim to analyze the characteristics of a photon converter in a medical LINAC using GEANT4 (Geometry and Tracking). For this, the photon and neutron spectrums of the optimized photon converter with tungsten were simulated with 2-24 MeV electron beams, and the ratio of photons with energies over 7.41 MV was analyzed.

Keywords: photon converter, photon target, medical LINAC, GEANT4.

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Cite this article

Ko Junho, Kim Beom Yeong, Kim Yoon Sang Characteristic analysis of a photon converter in a medical LINAC using GEANT4. Vibroengineering PROCEDIA, Vol. 14, 2017, p. 256‑259.

 

© JVE International Ltd. Vibroengineering PROCEDIA. Oct 2017, Vol. 14. ISSN 2345-0533