Dose perturbations at high-Z interfaces in kilovoltage photon beams: comparison with Monte Carlo simulations and measurements
作者： Indra J. Das , Vadim P. Moskvin , Alireza Kassaee , Tatsuo Tabata , Frank Verhaegen
DOI: 10.1016/S0969-806X(01)00460-1
关键词: Computation 、 Imaging phantom 、 Optics 、 Backscatter 、 Polynomial regression 、 Monte Carlo method 、 Bidirectional scattering distribution function 、 Measuring instrument 、 Radiation 、 Physics
摘要: Abstract Dose perturbations, backscatter dose perturbation factor (BSDF), and forward (FDPF) near high-Z material interfaces have been reported to be intense significant in kilovoltage photon beams. Validity of estimation perturbations is critical the evaluation radiation effects associated with interfaces. The magnitude has debated due limitations measuring devices (mainly window thickness chamber perturbations). Monte Carlo (MC) simulations proposed for interface but poor statistics small spatial bins (1 μm) makes MC data questionable even a well designed code. A moving-window least-square polynomial fit (MLPF) method smooth simulated data. This shown useful achieving reasonable accuracy from statistically obtained within computation time. EGS4 PENELOPE at between materials water phantom used calculate BSDF FDPF which differ significantly measurements suggesting necessity further refinements approaches better effects.
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