Absorbed dose from secondary electrons in high energy photon beams
- 1 September 1979
- journal article
- research article
- Published by IOP Publishing in Physics in Medicine & Biology
- Vol. 24 (5) , 901-912
- https://doi.org/10.1088/0031-9155/24/5/003
Abstract
The absorbed dose in high energy photon beams due to scattered electrons from the irradiated air volume and from beam-shaping platforms has been calculated using the Fermi-Eyges theory of multiple scattering. The results are presented as lateral surface absorbed dose distributions across the field for three different radiation qualities, namely 60Co, 6 MV and 21 MV X-rays. For 60Co the relative absorbed dose due to electrons expelled in air reaches a value as high as 30% of the absorbed dose at dose maximum at a field size 40*40 cm2 and an SSD of 100 cm. The absorbed dose from electrons emanating from beam-shaping platforms contribute significantly to the absorbed dose at the surface when the platform is placed closer than 20-40 cm from the surface for field sizes greater than 10*10 cm2 to 40*40 cm2 respectively.This publication has 21 references indexed in Scilit:
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