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Characteristics of Scattered Rays Depending on the Use of a Flattening Filter

선속평탄 여과판 사용 유무에 따른 산란선 특성

  • Received : 2016.01.03
  • Accepted : 2016.01.30
  • Published : 2016.01.30

Abstract

This Study aims at measuring scattered rays depending on the use of a flattening filter when radiation is irradiated using a linear accelerator. measurement of the scattered rays, an ionization chamber was used, and the energy of the irradiated radiation was 6 MV and 10 MV. The ionization chamber was located at the spot 15 cm, 25 cm, 35 cm and 45 cm far away from the center of gantry rotation, and the scattered rays were measured according to whether a flattening filter was used or not and to the distance. As the result of investigation of 100 cGy about each energy, when the flattening filter was not used with 6 MV, it occurred at a low level of 65%, and with 10 MV at that of 55%. In other words, it's been concluded that when a flattening filter is not used for radiation dose of the parts around the critical organ, scattered rays generate in a small quantity, and it's a useful way to decrease the stochastic effect of radiation.

Keywords

flattening filter;linear accelerator;scattered ray

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