'Track' - Monte Carlo code to model proton therapy beam modifying systems

Proton beams delivered by the accelerator, used for therapy, need to be modified before entering the patient in order to deliver the prescribed spatial dose distribution to the target. Small and medium proton fields are usually formed by a system of scatterers and collimators. Beam-losses in the vicinity of the patient should be minimized. 'Track' - a computer code to calculate beam profiles on the target after passing through a system of scatterers and collimators - has been developed. A physical model used in the code is presented. The results of simulations are in a good agreement with the experimental data. The developed code represents a fast and effective instrument to assist the design of beam scattering systems