| Full text | |
| Author(s): |
Total Authors: 2
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| Affiliation: | [1] Pontifícia Universidade Católica do Rio Grande do Sul. Grupo de Experimentação e Simulação Computacional em Física Médica - Brasil
[2] Universidade de São Paulo. Instituto de Física. Departamento de Física Nuclear - Brasil
Total Affiliations: 2
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| Document type: | Journal article |
| Source: | Rev. Bras. Eng. Bioméd.; v. 29, n. 1, p. 86-96, 2013-03-00. |
| Abstract | |
The aim of this work is to simulate transmission data for different beam geometry and material composition in order to evaluate the effect of these parameters on transmission curves. The simulations are focused on outgoing spectra for shielding barriers used in PET facilities. The behavior of the transmission was evaluated as a function of the shielding material composition and thickness using Geant4 Monte Carlo code, version 9.2 p 03.The application was benchmarked for barited mortar and compared to The American Association of Physicists in Medicine (AAPM) data for lead. Their influence on the transmission curves as well the study of the influence of the shielding material composition and beam geometry on the outgoing spectra were performed. Characteristics of transmitted spectra, such as shape, average energy and Half-Value Layer (HVL), were also evaluated. The Geant4 toolkit benchmark for the energy resulting from the positron annihilation phenomena and its application in transmission curves description shown good agreement between data published by American Association on Physicists in Medicine task group 108 and experimental data published by Brasil. The transmission properties for different material compositions were also studied and have shown low dependency with the considered thicknesses. The broad and narrow beams configuration presented significant differences on the result. The fitting parameter for determining the transmission curves equations, according to Archer model is presented for different material. As conclusion were defined that beam geometry has significant influence and the composition has low influence on transmission curves for shielding design for the range of energy applied to PET. (AU) | |
| FAPESP's process: | 10/12237-7 - Experimento evaluation of the relation between air-Kerma and ambient equivalent dose for shielding calculation in adult and pediatric X-ray rooms |
| Grantee: | Paulo Roberto Costa |
| Support Opportunities: | Regular Research Grants |