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PubMed · 8289717

A simple one-dimensional model for understanding planar dose-versus-depth profiles in mixed photon/electron fields.

D L Fehl
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Abstract

A one-dimensional model is described for illustrating the perturbing effects of mixed photon/electron fields on planar dose-versus-depth profiles in low Z materials (Z < or = 20), and at moderate photon energies (0.3-10 MeV). An electron field may arise from photon interactions in filters upstream of a dose-versus-depth experiment. The effects of upstream mass, scattering of electrons out of a gap between a filter and the experiment, and differences between the incident electron energy distribution and locally produced KERMA are modeled and compared to Discrete Ordinates calculations. At transitional depths in a dose-versus-depth experiment, the distortions can be significant and obscure the profile of the photon component alone.

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Biophysical PhenomenaBiophysicsElectronsModels, TheoreticalPhotonsRadiation DosageScattering, RadiationJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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D L Fehl. A simple one-dimensional model for understanding planar dose-versus-depth profiles in mixed photon/electron fields.. https://doi.org/10.1118/1.597100

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