Tomé W A, Palta J R
Department of Radiation Oncology, University of Florida, College of Medicine, Gainesville 32610-0385, USA.
Med Phys. 1998 May;25(5):758-72. doi: 10.1118/1.598258.
An analytical method for the calculation of ratios of mean restricted collision stopping powers (L/rho)(g)m averaged over the charged particle spectra and the photon spectrum that is accurate to first order has been developed, and it has been explored whether a moderate change in the photon fluence spectrum with field size has an effect on the mean restricted collision stopping power ratio in high-Z materials. The results of this study indicate that for the case of a miniphantom, moderate changes in the photon fluence spectrum have only a weak effect on the ratios of mean restricted collision stopping powers.