Comparative Study of Absorbed Doses in Different Phantom Materials and Fabrication of a Suitable Phantom
DOI:
https://doi.org/10.18034/mjmbr.v5i1.444Keywords:
Phantom, Dosimetry, Absorbed dose, Paraffin-wax, Scaling factorAbstract
In Cancer treatment (radiotherapy) centers, Phantom is important in Quality Assurance routine check and absolute dosimetry conformation. Water is IAEA standard phantom material. But it has some technical difficulty in practical uses and other solid phantoms such as Polystyrene, PMMA is very expensive and locally not available. Hence, the purpose of this paper is to find out a phantom that will be technically very sound, cost effective and locally available. This study reveals that paraffin wax, which has some approximately similar properties (i.e. chemical composition, mass density and number of electrons/gram) to water, can be used as alternative of solid water phantom because of their proximity to the dose absorption property of water which is even better than some of the conventional solid phantoms used in radiation dosimetry. It is also found that paraffin wax phantom with air-bubble inside behaves differently to the radiation absorbing dose and therefore in dose absorption and dose conversion (scaling) factor.
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