Autor: Monaliza de Oliveira Almeida, Matheus Rabello do Nascimento, Carlos Henrique Simões de Sousa, José Guilherme Pereira Peixoto
Resumo: The MC method makes it possible to assess the dose in diagnostic procedures and in studies of the quality of medical images. Half Value Layer can be defined as the thickness of absorbing material needed to reduce the intensity of the X-ray beam to 50% of the initial value, under conditions of good geometry. In view of this, it is possible to simulate, through the MC Method, situations and find values close to reality. The objective of this work is to investigate the use of the Monte Carlo simulation code EGSncr to calculate the Half Value Layers of shields aimed at Radiological Protection, stating its real need and estimating the thickness of the materials to be used in the shields. To carry out the simulations, 1 (one) Desktop computer with Linux Mint 20.1 Cinnamon operating system, Intel© Core™2 Duo Processor E8400 CPU @ 3.00GHz × 2, 3.7 GiB Memory, 160.1 GB Hard Disks; Monte Carlo EGSncr code for the construction of the simulations, where 15 cm diameter barium concrete discs were created, with thicknesses of 0.5, 1.0, 1.5 and 2.5, where x-ray beams of 70, 120 and 140 KeV. Thus, according to the results found, we can state that there is a lot of energy scattering, and that there is the necessary shielding to be able to have protection against the x-ray beams, confirming the effectiveness of the protection of the barium mixture, as shown. The simulation’s easing graphs show that the values are in line with what was expected. Therefore, we can state that the Monte Carlo simulation program EGSnrc is a reliable and efficient tool for experiments with x-ray beams.