A finite-element model of electron transport in radiation therapy and a related inverse problem

The paper considers the Galerkin finite-element approximation of the Boltzmann transport equation for charged particles. The aim is to model the electron transport in biological tissue for the dose calculation and to apply the method to planning of the treatment. The model takes into account multiple Coulomb scattering but it omits brehmsstrahlung and pair production. The differential multiple-scattering cross sections are computed from the screened Rutherford scattering formula by repeated convolutions. In the inverse problem a feasible solution is sought by the Cimmino algorithm. The preliminary simulation results show that refinements for practical situations are worth studying.

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