Computing Efficiency Improvement in Monte Carlo Simulation of a 12 MV Photon Beam Medical LINAC

M. Zoubair, T. El Bardouni, O. Allaoui, Y. Boulaich, B. El Bakkari, C. El Younoussi, H. Boukhal, E. Chakir

ERSN-LMR, Faculty of Sciences, University Abdelmalek Essaadi, Tetouan, Morocco.
Faculty of Sciences, University Ibn Tofail, Kénitra, Morocco.

DOI: 10.4236/wjnst.2013.31003                

Abstract

Variance reduction techniques (VRTs) have been tremendously successful when applied to Monte Carlo radiation transport codes for which the computation time constitutes an important and a problematic parameter. In fact, many Monte Carlo calculations absolutely require variance reduction methods to achieve practical computation times. The MCNPX code has a fairly rich set of variance reduction techniques; the most known are transport cutoffs, interaction forcing, Bremsstrahlung splitting and Russian roulette. Also, the use of a phase space seems to be appropriate to reduce enormously the computing time. This work deals with the use of VRTs provided by MCNPX code for the simulation of a clinical linear electron accelerator (LINAC). Differences between various sets of VRTs are investigated. Combination between VRTs and PS is also analyzed during this study. Analysis showed that the use of VRTs and PS improve the simulation efficiency by a factor greater than 700. Finally, experimental curves of depth-dose and dose profile performed in a homogeneous water phantom are compared to dose distributions computed by use of MCNPX Monte Carlo code.

Keywords

Variance Reduction Techniques; Phase Space; LINAC; Monte Carlo Simulation

Conflicts of Interest

The authors declare no conflicts of interest.

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