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A computer model of broad beam transmission through lead material for γ rays and X-rays of different energies

Published online by Cambridge University Press:  15 September 2010

Saud H. Al-lehyani*
Affiliation:
Department of Physics, Faculty of Applied Sciences, Umm Al-Qura University, Makkah, Kingdom of Saudi Arabia
*
Correspondence to: Saud H. Al-lehyani, Department of Physics, Faculty of Applied Sciences, Umm Al-Qura University, Makkah, P.O. Box. 10130, Kingdom of Saudi Arabia. Email: saud8882001@yahoo.com

Abstract

In radiotherapy, the radiation beam is sometimes shaped so as to deliver different doses to different organs or give a homogeneous dose to structures of different densities. This objective is achieved by the use of attenuating materials introduced into the radiation beam. These attenuators alter the primary as well as the scattered radiation components of the beam and there is at present no accurate method of dose calculation for these situations. Most calculations are performed considering only the effect of the attenuators on the primary radiation beam and can produce large errors in dosimetry. In this study, the broad-beam attenuation is investigated in homogeneous phantoms for various radiation field sizes, photon beam energies and depths in phantom. A mathematical method taking account of primary as well as first scattered radiation is developed. This method predicts reasonably well the transmission through lead attenuators for various experimental conditions.

Type
Original Article
Copyright
Copyright © Cambridge University Press 2010

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