Monte Carlo Modeling of the Elekta Precise Linear Accelerator: Validation of Dose Distribution in a Heterogeneous Water Phantom

The present work is devoted to develop a computational model using the Monte Carlo code MCNP5 (Monte Carlo N-Particle) for the simulation of a 6 MV photon beam given by Elekta Precise medical linear accelerator treatment head. The model includes the major components of the multileaf accelerator head and a cube-shaped water tank. Calculations were performed for a photon beam with 10 cm x 10 cm irradiation field at 100 cm distance from source. The simulation is able to predict the absorbed dose distribution within the water tank using the F8 or FMESH4 tally and the achieved results have been validated by comparison with experimental values measured at the Hospital Provincial de Castelló. Dosimetric parameters calculated at the phantom show a good agreement with the measured ones. Moreover, the parallelization of the MCNP5 code demonstrates that this simulation is not only an accurate tool to predict the energy deposition but also a fast way to obtain satisfactory results.