Novel Fundaments to Characterize and to Assess the Material Quality for High Photon Beam Filtration Efficiency

详细

The objective of this study is to introduce novel fundaments to characterize and assess the material behaviors on photon beam attenuation and beam softening for high filtration system quality. This study was done by Monte Carlo method using BEAMnrc code and BEAMDP code. After validation of Monte Carlo model of linear accelerator with flattening filter; the later was replaced by material slab of aluminum and copper with different thickness. The photon beam attenuation was evaluated for primary photon fluence and secondary photon fluence for checking the dependence on energy; the beam softening was also evaluated based on beam attenuation coefficients. Based on the beam softening coefficients that were correlated by attenuation coefficients, the softening index was introduced as a new parameter to assess the material effects for high filtration system quality. These novel fundaments allow assessing the quality of a material for high photon beam filtration system quality.