Monte Carlo Electron Dose Calculations Using Discrete Scattering Angles and Discrete Energy Losses

Numerical computation of discrete differential scattering cross sections for Monte Carlo charged particle transport

“…The high peaking of the Rutherford cross section towards zero-energy loss interactions is shown in Fig. 2, which compares the continuous cross section model to the discrete cross section values obtained through both our method and that of Franke and Prinja (2005). Again, relative differences between the two sets of discrete nodes (i.e.…”

“…Previous work by Franke and Prinja uses moment-preserving discrete scattering cross sections to speed up charged particle transport simulations relative to the single-event approach (Franke and Prinja, 2005). That work makes use of recursion relationships described by Morel (Morel, 1979) to generate modified moments of the weight function defined by the selected cross section model.…”

“…with the minimum energy loss, Q min , taken to be the mean excitation energy of the material through which the particle is traveling, as suggested by Franke and Prinja (2005). The orthogonal polynomial coefficients come from the monic Legendre polynomials.…”

“…The two processes for computing modified moments of the cross section weight function produce sets of discrete values that differ from one another. The relative differences in discrete scattering angles and energy losses, and corresponding cross section values computed with our method, as compared to the values computed with the method described by Franke and Prinja (2005), are shown in Figs. 1 and 2.…”

“…Options for this sort of modified cross section data include discrete differential scattering angle and energy loss cross section values (Franke and Prinja, 2005) and cross section values obtained from simplified continuous models. Any method for improving the computational efficiency of a simulation should also preserve the essential physics of singleevent methods so as to retain the accuracy of the transport solution.…”