Using Monte Carlo simulations to commission photon beam output factors--a feasibility study.

摘要: This study investigates the feasibility of using Monte Carlo methods to assist commissioning photon beam output factors from a medical accelerator. The code, BEAMnrc, was used model 6 MV and 18 beams Varian linear When excellent agreements were obtained between simulated measured dose distributions in water phantom, entire geometry including accelerator head phantom calculate relative factors. Simulated compared with data, which consist typical commission dataset for measurements done an ionization chamber at depth 10 cm source-detector distance 100 cm. Square fields rectangular widths lengths ranging 4 40 studied. result shows very good agreement (< 1.5%) calculated dataset. backscatter monitor agree well data literature. simulations have also been shown be able accurately predict collimator exchange effect its component fields. information is useful develop algorithm accurate modelling. investigation indicates that can beams.